Monoacylglycerol lipase modulators for use in autism spectrum disorders

ABSTRACT

The disclosure relates to certain uses and methods of use of 3.1.0 and 4.1.0 azabicycle compounds of Formula (I), wherein X, Y, R 1 , R 2a , and R 2b  are defined herein, and pharmaceutical compositions containing them, in the treatment of autism spectrum disorder, including Asperger&#39;s syndrome.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No. 63/231,094, filed Aug. 9, 2021, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to certain uses and methods of use of 3.1.0 and 4.1.0 azabicycle chemical entities having MGL modulating properties, and pharmaceutical compositions comprising these chemical entities, in the treatment of autism spectrum disorder, including Asperger's syndrome.

BACKGROUND OF THE INVENTION

Cannabis sativa and analogs of Δ⁹-tetrahydrocannabinol have been used since the days of folk medicine for therapeutic purposes. The endocannabinoid system consists of two G-protein coupled receptors, cannabinoid receptor type 1 (CB1) (Matsuda et al., Nature, 1990, 346, 561-4) and cannabinoid receptor type 2 (CB2) (Munro et al., Nature, 1993, 365, 61-5). CB1 receptor is one of the most abundant G-protein coupled receptor expressed in the brain (Herkenam et al., Proc. Nat. Acad. Sci., 1990, 87(5), 1932-1936). CB1 is also expressed peripherally in the liver, gastrointestinal tract, pancreas, adipose tissue, and skeletal muscles (Di Marzo et al., Curr. Opin. Lipidol., 2007, 18, 129-140). CB2 is predominantly expressed in immune cells such as monocytes (Pacher et al., Amer. J. Physiol., 2008, 294, H1133-H1134) and under certain conditions (inflammation) in the brain ((Benito et al., Brit. J. Pharmacol., 2008, 153, 277-285) and in skeletal (Cavuoto et al., Biochem. Biophys. Res. Commun., 2007, 364, 105-110) and cardiac muscles (Hajrasouliha et al., Eur. J. Pharmacol., 2008, 579, 246-252).

In 1992, N-arachidonoylethanolamine (AEA or anandamide) was found to be an endogenous ligand for cannabinoid receptors (Devane et al., Science, 1992, 258, 1946-9). Subsequently, 2-arachidonoylglycerol (2-AG) was identified as an additional endogenous ligand for the cannabinoid receptors (Mechoulam et al., Biochem. Pharmacol., 1995, 50, 83-90; Sugiura et al., Biochem. Biophys. Res. Commun., 1995, 215, 89-97). Concentrations of 2-AG were reported to be at least 100 times higher than those of anandamide in the rat brain (Buczynski and Parsons, Brit. J. Pharmacol., 2010, 160 (3), 423-42). Therefore, 2-AG may play more essential physiological roles than anandamide in the brain endocannabinoid system (Sugiura et al. Prostaglandins Leukot. Essent. Fatty Acids., 2002, 66(2-3), 173-92). The endocannabinoid 2-AG is a full agonist for CB1 and CB2 receptors, while anandamide is a partial agonist for both receptors (Suguira et al., Prog. Lipid Res., 2006, 45(5), 405-46). Unlike many classical neurotransmitters, endocannabinoids signal through a retrograde mechanism. They are synthesized on demand in postsynaptic neurons and then rapidly degraded following binding to presynaptic cannabinoid receptors (Ahn et al., Chem. Rev., 2008, 108(5), 1687-707). Monoacylglycerol lipase (MGLL, also known as MAG lipase and MGL) is the serine hydrolase responsible for the degradation of 2-AG into arachidonic acid and glycerol in the central nervous system (Mechoulam et al., Biochem. Pharmacol., 1995, 50, 83-90; Sugiura et al., Biochem. Biophys. Res. Commun.,supra; Long et al., Nat. Chem. Biol., 2009, 5(1), 37-44), Schlosburg et al., Nat. Neurosci., 2010, 13(9), 1113-9) and peripheral tissues (Long et al., Chem. Biol., 2009, 16(7), 744-53). Anandamide is hydrolyzed by fatty acid amide hydrolase (FAAH) (Piomelli, Nat. Rev. Neurosci., 2003, 4, 873-884). MGL exists in both soluble and membrane bound forms (Dinh et al., Proc. Natl. Acad. Sci. U.S.A., 2002, 99(16), 10819-24). In the brain MGL is located in presynaptic neurons (Straiker et al., Mol. Pharmacol., 2009, 76(6), 1220-7) and astrocytes (Walter et al., J. Neurosci., 2004, 24(37), 8068-74) within regions associated with high CB1 receptor density. Compared to wild-type controls, genetic ablation of MGL expression produces 10-fold increase in brain 2-AG levels without affecting anandamide concentration (Schlosburg et al., Nat. Neurosci., 2010, 13(9), 1113-9).

Thus, MGL modulation offers an interesting strategy for potentiating the cannabinoid system. The primary advantage of this approach is that only brain regions where endocannabinoids are actively produced will be modulated, potentially minimizing the side effects associated with exogenous CB1 agonists. Pharmacological inactivation of MGL by covalent inhibitors in animals increase 2-AG content in brain and peripheral tissues and has been found to produce antinociceptive, anxiolytic and anti-inflammatory effects that are dependent on CB1 and/or CB2 receptors (Long et al., Nat. Chem. Biol., 2009, 5(1), 37-44; Ghosh et al., Life Sci., 2013, 92(8-9), 498-505; Bedse et al., Biol. Psychiatry, 2017, 82(7), 488-499; Bernal-Chico et al., Glia, 2015, 63(1), 163-76; Patel et al., Neurosci. Biobehav. Rev., 2017, 76(Pt A), 56-66; Bedse et al., Transl. Psychiatry, 2018, 8(1), 92). In addition to the role of MGL in terminating 2-AG signaling, MGL modulation, including MGL inhibition, also promotes CB1/2-independent effects on neuroinflammation (Nomura et al., Science, 2011, 334(6057), 809-13). MGL modulation, including MGL inhibition, leads to reduction in proinflammatory prostanoid signaling in animal models of traumatic brain injury (Katz et al., J. Neurotrauma, 2015, 32(5), 297-306; Zhang et al., J. Cereb. Blood Flow Metab., 2015, 35(4), 443-453), neurodegeneration including Alzheimer's disease (Piro et al., Cell Rep., 2012, 1(6), 617-23; Wenzel et al., Life Sci., 2018, 207, 314-322; Chen et al., Cell Rep., 2012, 2(5), 1329-39), Parkinson's disease (Nomura et al., Science, 2011, 334(6057), 809-13; Pasquarelli et al., Neurochem. Int., 2017, 110, 14-24), amyotrophic lateral sclerosis (Pasquarelli et al., Neuropharmacology, 2017, 124:157-169), multiple sclerosis (Hernadez-Torres et al., Angew. Chem. Int. Ed. Engl., 2014, 53(50), 13765-70; Bernal-Chico et al., Glia, 2015, 63(1), 163-76), Huntington's disease (Covey et al., Neuropsychopharmacology, 2018, 43, 2056-2063), Tourette syndrome and status epilepticus (Terrone et al., Epilepsia, 2018, 59(1), 79-91; von Ruden et al., Neurobiol. Dis., 2015, 77, 238-45).

Therefore, by potentiating the cannabinoid system and attenuating proinflammatory cascades, MGL modulation, including MGL inhibition, offers a compelling therapeutic approach for the treatment of a vast array of complex neurological diseases. Importantly, MGL modulation, including MGL inhibition in animals, does not produce the full spectrum of neurobehavioral effects observed with Δ⁹-tetrahydrocannabinol and other CB1 agonists (Tuo et al., J. Med. Chem., 2017, 60(1), 4-46; Mulvihill et al., Life Sci., 2013, 92(8-9), 492-7).

Endocannabinoid hypoactivity is a risk factor for the treatment of depression, anxiety, and post-traumatic stress disorders. Millennia of human use of Cannabis sativa, and a brief period in which humans were treated with the endocannabinoid antagonist, rimonabant, provide support for that hypothesis. 2-AG levels are decreased in individuals with major depression (Hill et al., Pharmacopsychiatry, 2008, 41(2), 48-53; Hill et al., Psychoneuroendocrinology, 2009, 34(8), 1257-1262). Low circulating 2-AG levels predict rates of depression (Hauer et al., Rev. Neurosci., 2012, 23(5-6), 681-90). Reduced circulating 2-AG has been found in patients with post-traumatic stress disorder (PTSD) (Hill et al., Psychoneuroendocrinology, 2013, 38(12), 2952-2961). Healthy volunteers exposed to chronic stressors exhibited progressively diminished circulating 2-AG levels which correlated with the onset of reductions in measures of positive emotions (Yi et al., Prog. Psychopharmacol. Biol. Psychiatry, 2016, 67(3), 92-97). The CB1 receptor inverse agonist/antagonist, rimonabant, has been withdrawn from the market due to the high incidence of severe depression and suicidal ideation (Christensen et al., The Lancet, 2007, 370, 1706-1713). Therefore, MGL modulators are potentially useful for the treatment of mood disorders, anxiety, and PTSD.

Autism spectrum disorder (ASD) is a neurodevelopmental disability that can cause significant social, communication, and behavioral challenges. ASD includes several conditions that have been diagnosed separately, including autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS), and Asperger's syndrome (DSM-V), and is commonly referred to in the ICD-10 system as autistic disorder. Because the endocannabinoid system regulates several central nervous system functions, including motor functions such as motor control and repetitive behaviors, cognitive functions such as perception, learning, and memory, mood functions such as anxiety and stress, and social behaviors, which are hallmark symptoms of autism spectrum disorder (ASD), this system provides a potential target for treatment for ASD and related disorders. In several preclinical animal models of ASD, augmentation of the endocannabinoid 2-AG via pharmacological inhibition of MGL has demonstrated significant effects in reversing many molecular, electrophysiological, and behavioral deficits (Folkes et al., J. Clin. Invest., 2020, 130(4), 1728-1742; Jung et al., Nat. Commun., 2012, 3, 1080; Wang et al., Mol. Psychiatry, 2018, 23(8), 1798-1806). The endocannabinoid system may mediate stress and/or anxiety that may impair social interaction: there is evidence of this effect in preclinical models (Marco et al., Behav. Brain Res. 2011, 220(1), 140-145). The neurobiologic understanding of autism is further informed by genetic models of ASD: preclinical mouse models, along with pharmacologic models, of ASD implicate the extensive role of endocannabinoid system in ASD core symptoms (Pietropaolo et al., Prog. Mol. Biol. Transl. Sci. 2020, 173, 183-208). While two drugs (risperidone and aripiprazole) are approved in the United States for the treatment of irritability associated with autistic disorder, including symptoms of aggression, deliberate self-injury, temper tantrums, and quickly changing moods, these symptoms are not core to the diagnosis of ASD. There are no FDA-approved pharmacological treatments for the array of core ASD symptoms—social communication, sensory hypersensitivity, and restricted, repetitive behaviors. Thus, there is a significant unmet need for new pharmacological interventions for ASD across the age spectrum.

SUMMARY OF THE INVENTION

Embodiments of the present invention relate to certain uses and methods of use of 3.1.0 and 4.1.0 azabicycle chemical entities having MGL modulating properties, and pharmaceutical compositions comprising these chemical entities, in the treatment of autism spectrum disorder including related disorders.

The autism spectrum disorder may include autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS), Asperger's syndrome, Fragile X syndrome, Rett syndrome, childhood disintegrative disorder, Kanner's syndrome, Phelan McDermid Syndrome, Angelman syndrome, SCN2a related autism, SYNGAP related autism, Dub15q related autism, Dyrk1a related autism, GRIN2B related autism, Malan syndrome, ADNP syndrome, or tuberous sclerosis. Specifically, the autism spectrum disorder encompasses autistic disorder or Asperger's syndrome. Treatment with the 3.1.0 and 4.1.0 azabicycle chemical entities having MGL modulating properties of the present application may improve social interaction of the subject, which can be observed as an increase of the subject's interest in social novelty.

Additional embodiments, features, and advantages of the invention will be apparent from the following detailed description and through practice of the invention.

Embodiments of this invention are uses and methods of treatment using compounds of Formula (I),

wherein

-   X is CH₂ or O; -   Y is

-   R¹ is H; -   R^(2a) and R^(2b) are each H; -   R³ is 2,3-dihydro-1H-indene; pyridyl substituted with C₁₋₆alkyl;     phenyl; or phenyl substituted with one or two members each     independently selected from the group consisting of: halo,     C₁₋₆alkyl, C₁₋₆alkyl substituted with OH, C₁₋₆alkyl substituted with     CO₂H, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, O-phenyl, and     C₃₋₆cycloalkyl substituted with CH₃; -   R^(a) and R^(b) are each independently H or halo; and -   R^(c) is H or CH₃;     or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or     stereoisomer thereof.

These and other aspects of the invention will become apparent to those skilled in the art after a reading of the following detailed description of the invention, including the figures and appended claims.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A shows the amount of time test mice spent exploring familiar mouse chamber and stimulus mouse chamber after administration of either placebo or the compound of Example 78 according to an exemplary three-chamber sociability test of Biologic Example 3.

FIG. 1B shows the number of entries test mice entered into familiar mouse chamber and stimulus mouse chamber after administration of either placebo or the compound of Example 78 according to an exemplary three-chamber sociability test of Biologic Example 3.

FIG. 1C shows the amount of time test mice spent interacting with familiar mouse or stimulus mouse after administration of either placebo or the compound of Example 78 according to an exemplary three-chamber sociability test of Biologic Example 3.

FIG. 1D shows the number of interactions with the C57BL/6 or BTBR mouse had with familiar mouse or stimulus mouse after administration of either placebo or the compound of Example 78 according to an exemplary three-chamber sociability test of Biologic Example 3.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the terms “including”, “containing” and “comprising” are used in their open, non-limiting sense.

Unless qualified specifically in particular instances of use, the term “alkyl” refers to a straight- or branched-chain alkyl group having from 1 to 8 carbon atoms in the chain. Examples of alkyl groups include methyl (Me), ethyl (Et), n-propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl (tBu), pentyl, isopentyl, tert-pentyl, hexyl, isohexyl, and groups that in light of the ordinary skill in the art and the teachings provided herein would be considered equivalent to any one of the foregoing examples. “C₁₋₆alkyl” refers to straight- or branched-chain alkyl group having from 1 to 6 carbon atoms in the chain. “C₁₋₄alkyl” refers to straight- or branched-chain alkyl group having from 1 to 4 carbon atoms in the chain.

The term “cycloalkyl” refers to a saturated or partially saturated, monocyclic, fused polycyclic, or spiro polycyclic carbocycle having from 3 to 12 ring atoms per carbocycle. Illustrative examples of cycloalkyl groups include the following entities, in the form of properly bonded moieties:

The term “3.1.0 azabicycle” refers to a bicyclic bridged compounds that contain a nitrogen. Illustrative example of 3.1.0 azabicycle group include the following entities, in the form of properly bonded moieties:

The term “4.1.0 azabicycle” refers to a bicyclic bridged compounds that contain a nitrogen. Illustrative example of 4.1.0 azabicycle groups include the following entities, in the form of properly bonded moieties:

The term “halogen” or “halo” represents chlorine, fluorine, bromine, or iodine.

The term “haloalkyl” refers to a straight- or branched-chain alkyl group having from 1 to 6 carbon atoms in the chain optionally substituting hydrogens with halogens. The term “C₁₋₄ haloalkyl” as used here refers to a straight- or branched-chain alkyl group having from 1 to 4 carbon atoms in the chain, optionally substituting hydrogens with halogens. Examples of “haloalkyl” groups include trifluoromethyl (CF₃), difluoromethyl (CF₂H), monofluoromethyl (CH₂F), pentafluoroethyl (CF₂CF₃), tetrafluoroethyl (CHFCF₃), monofluoroethyl (CH₂CH₂F), trifluoroethyl (CH₂CF₃), tetrafluorotrifluoromethylethyl (CF(CF₃)₂), and groups that in light of the ordinary skill in the art and the teachings provided herein would be considered equivalent to any one of the foregoing examples.

The term “aryl” refers to a monocyclic, aromatic carbocycle (ring structure having ring atoms that are all carbon) having 6 atoms per ring (Carbon atoms in the aryl groups are sp2 hybridized.)

The term “phenyl” represents the following moiety:

Those skilled in the art will recognize that the species of 3.1.0 azabicycle, 4.1.0 azabicycle, cycloalkyl or aryl groups listed or illustrated above are not exhaustive, and that additional species within the scope of these defined terms may also be selected.

The term “substituted” means that the specified group or moiety bears one or more substituents. The term “unsubstituted” means that the specified group bears no substituents. The term “optionally substituted” means that the specified group is unsubstituted or substituted by one or more substituents. Where the term “substituted” is used to describe a structural system, the substitution is meant to occur at any valency-allowed position on the system.

The term “variable point of attachment” means that a group is allowed to be attached at more than one alternative position in a structure. The attachment will always replace a hydrogen atom on one of the ring atoms. In other words, all permutations of bonding are represented by the single diagram, as shown in the illustrations below.

Those skilled in the art will recognize that that if more than one such substituent is present for a given ring, the bonding of each substituent is independent of all of the others. The groups listed or illustrated above are not exhaustive.

The term “substituted” means that the specified group or moiety bears one or more substituents. The term “unsubstituted” means that the specified group bears no substituents. The term “optionally substituted” means that the specified group is unsubstituted or substituted by one or more substituents. Where the term “substituted” is used to describe a structural system, the substitution is meant to occur at any valency-allowed position on the system.

Any formula given herein is intended to represent compounds having structures depicted by the structural formula as well as certain variations or forms. In particular, compounds of any formula given herein may have asymmetric centers and therefore exist in different enantiomeric forms. All optical isomers and stereoisomers of the compounds of the general formula, and mixtures thereof, are considered within the scope of such formula. The compounds of this invention may possess one or more asymmetric centers; such compounds can therefore be produced as individual (R)- or (S)-stereoisomers or as mixtures thereof. Thus, any formula given herein is intended to represent a racemate, one or more of its enantiomeric forms, one or more of its diastereomeric forms, and mixtures thereof. Additionally, any formula given herein is intended to refer also to any one of: hydrates, solvates, polymorphs and of such compounds, and mixtures thereof, even if such forms are not listed explicitly.

The term “R” at a stereocenter designates that the stereocenter is purely of the R-configuration as defined in the art; likewise, the term “S” means that the stereocenter is purely of the S-configuration. As used herein, the term “RS” refers to a stereocenter that exists as a mixture of the R- and S-configurations.

Compounds containing one stereocenter drawn without a stereo bond designation are a mixture of 2 enantiomers. Compounds containing 2 stereocenters both drawn without stereo bond designations are a mixture of 4 diastereomers. Compounds with 2 stereocenters both labeled “RS” and drawn with stereo bond designations are a 2-component mixture with relative stereochemistry as drawn. Unlabeled stereocenters drawn without stereo bond designations are a mixture of the R- and S-configurations. For unlabeled stereocenters drawn with stereo bond designations, the absolute stereochemistry is as depicted.

Reference to a compound herein stands for a reference to any one of: (a) the actually recited form of such compound, and (b) any of the forms of such compound in the medium in which the compound is being considered when named. For example, reference herein to a compound such as R—COOH, encompasses reference to any one of: for example, R—COOH(s), R—COOH(sol), and R—COO-(sol). In this example, R—COOH(s) refers to the solid compound, as it could be for example in a tablet or some other solid pharmaceutical composition or preparation; R—COOH(sol) refers to the undissociated form of the compound in a solvent; and R—COO-(sol) refers to the dissociated form of the compound in a solvent, such as the dissociated form of the compound in an aqueous environment, whether such dissociated form derives from R—COOH, from a salt thereof, or from any other entity that yields R—COO— upon dissociation in the medium being considered. In another example, an expression such as “exposing an entity to compound of formula R—COOH” refers to the exposure of such entity to the form, or forms, of the compound R—COOH that exists, or exist, in the medium in which such exposure takes place. In still another example, an expression such as “reacting an entity with a compound of formula R—COOH” refers to the reacting of (a) such entity in the chemically relevant form, or forms, of such entity that exists, or exist, in the medium in which such reacting takes place, with (b) the chemically relevant form, or forms, of the compound R—COOH that exists, or exist, in the medium in which such reacting takes place. In this regard, if such entity is for example in an aqueous environment, it is understood that the compound R—COOH is in such same medium, and therefore the entity is being exposed to species such as R—COOH(aq) and/or R—COO-(aq), where the subscript “(aq)” stands for “aqueous” according to its conventional meaning in chemistry and biochemistry. A carboxylic acid functional group has been chosen in these nomenclature examples; this choice is not intended, however, as a limitation but it is merely an illustration. It is understood that analogous examples can be provided in terms of other functional groups, including but not limited to hydroxyl, basic nitrogen members, such as those in amines, and any other group that interacts or transforms according to known manners in the medium that contains the compound.

Such interactions and transformations include, but are not limited to, dissociation, association, tautomerism, solvolysis, including hydrolysis, solvation, including hydration, protonation, and deprotonation. No further examples in this regard are provided herein because these interactions and transformations in a given medium are known by any one of ordinary skill in the art.

Any formula given herein is also intended to represent unlabeled forms as well as isotopically labeled forms of the compounds. Isotopically labeled compounds have structures depicted by the formulas given herein except that one or more atoms are replaced by an atom having a selected atomic mass or mass number in an enriched form. Examples of isotopes that can be incorporated into compounds of the invention in a form that exceeds natural abundances include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine, chlorine, and iodine, such as ²H (or chemical symbol D), ³H (or chemical symbol T), ¹¹C, ¹³C, ¹⁴C, ¹⁵N, ¹⁸O, ¹⁷O, ³¹P, ³²P, ³⁵S, ¹⁸F, ³⁶Cl, and ¹²⁵I, respectively. Such isotopically labelled compounds are useful in metabolic studies (preferably with ¹⁴C), reaction kinetic studies (with, for example ²H or ³H), detection or imaging techniques [such as positron emission tomography (PET) or single-photon emission computed tomography (SPECT)] including drug or substrate tissue distribution assays, or in radioactive treatment of patients. In particular, an F or ¹¹C labeled compound may be particularly preferred for PET or SPECT studies. Further, substitution with heavier isotopes such as deuterium (i.e., ²H, or D) may afford certain therapeutic advantages resulting from greater metabolic stability, for example increased in vivo half-life or reduced dosage requirements. Isotopically labeled compounds of this invention can generally be prepared by carrying out the procedures disclosed in the schemes or in the examples and preparations described below by substituting a readily available isotopically labeled reagent for a non-isotopically labeled reagent.

When referring to any formula given herein, the selection of a particular moiety from a list of possible species for a specified variable is not intended to define the same choice of the species for such variable appearing elsewhere. In other words, where a variable appears more than once, the choice of the species from a specified list is independent of the choice of the species for the same variable elsewhere in the formula, unless stated otherwise.

The term C_(n-m) alkyl refers to an aliphatic chain, whether straight or branched, with a total number N of carbon members in the chain that satisfies n≤N≤m, with m>n.

When the same plurality of substituents is assigned to various groups, the specific individual substituent assignment to each of such groups is meant to be independently made with respect to the specific individual substituent assignments to the remaining groups. By way of illustration, but not as a limitation, if each of groups Q and R can be H or F, the choice of H or F for Q is made independently of the choice of H or F for R, so the choice of assignment for Q does not determine or condition the choice of assignment for R, or vice-versa, unless it is expressly indicated otherwise. Illustrative claim recitation in this regard would read as “each of Q and R is independently H or F”, or “each of Q and R is independently selected from the group consisting of H and F”.

Unless indicated otherwise, the description or naming of a particular compound in the specification and claims is intended to include both individual enantiomers and mixtures, racemic or otherwise, thereof. The methods for the determination of stereochemistry and the separation of stereoisomers are well-known in the art.

In another example, a zwitterionic compound would be encompassed herein by referring to a compound that is known to form a zwitterion, even if it is not explicitly named in its zwitterionic form. Terms such as zwitterion, zwitterions, and their synonyms zwitterionic compound(s) are standard IUPAC-endorsed names that are well known and part of standard sets of defined scientific names. In this regard, the name zwitterion is assigned the name identification CHEBI:27369 by the Chemical Entities of Biological Interest (ChEBI) dictionary of molecular entities. As generally well known, a zwitterion or zwitterionic compound is a neutral compound that has formal unit charges of opposite sign. Sometimes these compounds are referred to by the term “inner salts”. Other sources refer to these compounds as “dipolar ions”, although the latter term is regarded by still other sources as a misnomer. As a specific example, aminoethanoic acid (the amino acid glycine) has the formula H₂NCH₂COOH, and it exists in some media (in this case in neutral media) in the form of the zwitterion ⁺H₃NCH₂COO⁻. Zwitterions, zwitterionic compounds, inner salts and dipolar ions in the known and well-established meanings of these terms are within the scope of this invention, as would in any case be so appreciated by those of ordinary skill in the art. Because there is no need to name each and every embodiment that would be recognized by those of ordinary skill in the art, no structures of the zwitterionic compounds that are associated with the compounds of this invention are given explicitly herein. They are, however, part of the embodiments of this invention. No further examples in this regard are provided herein because the interactions and transformations in a given medium that lead to the various forms of a given compound are known by any one of ordinary skill in the art.

When referring to any formula given herein, the selection of a particular moiety from a list of possible species for a specified variable is not intended to define the same choice of the species for the variable appearing elsewhere. In other words, where a variable appears more than once, the choice of the species from a specified list is independent of the choice of the species for the same variable elsewhere in the formula, unless stated otherwise.

By way of a first example on substituent terminology, if substituent S¹ _(example) is one of S₁ and S₂, and substituent S² _(example) is one of S₃ and S₄, then these assignments refer to embodiments of this invention given according to the choices S¹ _(example) is S₁ and S² _(example) is S₃; S¹ _(example) is S₁ and S² _(example) is S₄; S¹ _(example) is S₂ and S² _(example) is S₃; S¹ _(example) is S₂ and S² _(example) is S₄; and equivalents of each one of such choices. The shorter terminology “S¹ _(example) is one of S₁ and S₂, and S² _(example) is one of S₃ and S₄” is accordingly used herein for the sake of brevity, but not by way of limitation. The foregoing first example on substituent terminology, which is stated in generic terms, is meant to illustrate the various substituent assignments described herein.

Furthermore, when more than one assignment is given for any member or substituent, embodiments of this invention comprise the various groupings that can be made from the listed assignments, taken independently, and equivalents thereof. By way of a second example on substituent terminology, if it is herein described that substituent S_(example) is one of S₁, S₂, and S₃, this listing refers to embodiments of this invention for which S_(example) is S₁; S_(example) is S₂; S_(example) is S₃; S_(example) is one of S₁ and S₂; S_(example) is one of S₁ and S₃; S_(example) is one of S₂ and S₃; S_(example) is one of S₁, S₂ and S₃; and S_(example) is any equivalent of each one of these choices. The shorter terminology “S_(example) is one of S₁, S₂, and S₃” is accordingly used herein for the sake of brevity, but not by way of limitation. The foregoing second example on substituent terminology, which is stated in generic terms, is meant to illustrate the various substituent assignments described herein.

The nomenclature “C_(i)-C_(j)” with j>i, when applied herein to a class of substituents, is meant to refer to embodiments of this invention for which each and every one of the number of carbon members, from i to j including i and j, is independently realized. By way of example, the term C₁-C₃ or C₁₋₃ refers independently to embodiments that have one carbon member (C₁), embodiments that have two carbon members (C₂), and embodiments that have three carbon members (C₃).

A “pharmaceutically acceptable salt” is intended to mean a salt of an acid or base of a compound represented by Formula (I) that is non-toxic, biologically tolerable, or otherwise biologically suitable for administration to the subject. See, generally, S. M. Berge, et al., “Pharmaceutical Salts,” J. Pharm. Sci., 1977, 66:1-19, and Handbook of Pharmaceutical Salts, Properties, Selection, and Use, Stahl and Wermuth, Eds., Wiley-VCH and VHCA, Zurich, 2002. Preferred pharmaceutically acceptable salts are those that are pharmacologically effective and suitable for contact with the tissues of patients without undue toxicity, irritation, or allergic response.

A compound of Formula (I) may possess a sufficiently acidic group, a sufficiently basic group, or both types of functional groups, and accordingly react with a number of inorganic or organic bases, and inorganic and organic acids, to form a pharmaceutically acceptable salt.

Examples of pharmaceutically acceptable salts include sulfates, pyrosulfates, bisulfates, sulfites, bisulfites, phosphates, monohydrogen-phosphates, dihydrogenphosphates, metaphosphates, pyrophosphates, chlorides, bromides, iodides, acetates, propionates, decanoates, caprylates, acrylates, formates, isobutyrates, caproates, heptanoates, propiolates, oxalates, malonates, succinates, suberates, sebacates, fumarates, maleates, butyne-1,4-dioates, hexyne-1,6-dioates, benzoates, chlorobenzoates, methylbenzoates, dinitrobenzoates, hydroxybenzoates, methoxybenzoates, phthalates, sulfonates, xylenesulfonates, phenylacetates, phenylpropionates, phenylbutyrates, citrates, lactates, γ-hydroxybutyrates, glycolates, tartrates, methane-sulfonates, propanesulfonates, naphthalene-1-sulfonates, naphthalene-2-sulfonates, and mandelates.

Compounds of Formula (I) may contain at least one nitrogen of basic character, so desired pharmaceutically acceptable salts may be prepared by any suitable method available in the art, for example, treatment of the free base with an inorganic acid, such as hydrochloric acid, hydrobromic acid, sulfuric acid, sulfamic acid, nitric acid, boric acid, phosphoric acid, and the like, or with an organic acid, such as acetic acid, phenylacetic acid, propionic acid, stearic acid, lactic acid, ascorbic acid, maleic acid, hydroxymaleic acid, isethionic acid, succinic acid, valeric acid, fumaric acid, malonic acid, pyruvic acid, oxalic acid, glycolic acid, salicylic acid, oleic acid, palmitic acid, lauric acid, a pyranosidyl acid, such as glucuronic acid or galacturonic acid, an alpha-hydroxy acid, such as mandelic acid, citric acid, or tartaric acid, an amino acid, such as aspartic acid or glutamic acid, an aromatic acid, such as benzoic acid, 2-acetoxybenzoic acid, naphthoic acid, or cinnamic acid, a sulfonic acid, such as laurylsulfonic acid, p-toluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, any compatible mixture of acids such as those given as examples herein, and any other acid and mixture thereof that are regarded as equivalents.

Compounds of Formula (I) may contain a carboxylic acid moiety, a desired pharmaceutically acceptable salt may be prepared by any suitable method, for example, treatment of the free acid with an inorganic or organic base, such as an amine (primary, secondary or tertiary), an alkali metal hydroxide, alkaline earth metal hydroxide, any compatible mixture of bases such as those given as examples herein, and any other base and mixture thereof that are regarded as equivalents or acceptable substitutes in light of the ordinary level of skill in this technology. Illustrative examples of suitable salts include organic salts derived from amino acids, such as glycine and arginine, ammonia, carbonates, bicarbonates, primary, secondary, and tertiary amines, and cyclic amines, such as benzylamines, pyrrolidines, piperidine, morpholine, piperazine, N-methyl-glucamine and tromethamine and inorganic salts derived from sodium, calcium, potassium, magnesium, manganese, iron, copper, zinc, aluminum, and lithium.

The compounds of the invention, including their pharmaceutically acceptable salts, whether alone or in combination, (collectively, “active agent” or “active agents”) of the present invention are useful as MGL-modulators in the methods of the invention. Such methods for modulating MGL comprise the use of a therapeutically effective amount of at least one chemical entity of the invention.

In some embodiments, the MGL modulator is an inhibitor and is used in a subject diagnosed with or suffering from autism spectrum disorder (ASD), including ASD, autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS), Asperger's syndrome, Fragile X syndrome, Rett syndrome, childhood disintegrative disorder, Kanner's syndrome, Phelan McDermid Syndrome, Angelman syndrome, SCN2a related autism, SYNGAP related autism, Dub15q related autism, Dyrk1a related autism, GRIN2B related autism, Malan syndrome, ADNP syndrome, or tuberous sclerosis. Symptoms or disease states are intended to be included within the scope of the diseases described herein. Symptoms of ASD include, but are not limited to, reduced eye contact, lack of response to name, indifference to caregivers, social withdrawal, aggression, towards self or others (including self-injurious behaviors), reduced or delayed language skills, delayed movement skills, delayed cognitive or learning skills, learning difficulties, delayed speech development, repetitive language, lack of emotional expression, repetitive movements (such as rocking, spinning, hand flapping, jumping, twirling), hypersensitivity to light, sound, or touch, hyperactivity, impulsive and/or inattentive behavior, excessive fixation on activities or objects, need for sameness or hyper-reactivity to environmental change, epilepsy or seizure disorder, gastrointestinal issues, anxiety, depression, and stress.

Accordingly, the invention relates to methods of using the active agents described herein to treat subjects diagnosed with or suffering from autism spectrum disorder. The term “treat” or “treating” as used herein is intended to refer to administration of an active agent or composition of the invention to a subject for the purpose of effecting a therapeutic or prophylactic benefit through modulation of MGL receptor activity or MGL modulation of endocannabinoid receptors. Treating includes reversing, ameliorating, alleviating, inhibiting the progress of, lessening the severity of, or preventing autism spectrum disorder, or one or more symptoms thereof that are associated with MGL modulation. The term “subject” refers to a mammalian patient in need of such treatment, such as a human.

In one exemplary embodiment, methods of using the active agents described herein to treat subjects diagnosed with or suffering from autism spectrum disorder are provided. The method may include administration the active agents described herein, in particular the compound of Example 78, either as a free base or a pharmaceutically acceptable salt thereof, to improve the subject's social interaction (e.g., social communication). Improvements in the subject's social interaction may be demonstrated, for example, in an increased interest (e.g., demonstrated by increased in duration or frequency) in social novelty.

The term “composition” refers to a product that includes the specified ingredients in therapeutically effective amounts, as well as any product that results, directly, or indirectly, from combinations of the specified ingredients in the specified amounts.

The term “MGL inhibitor” is intended to encompass a compound that interacts with MGL to substantially reduce or eliminate its catalytic activity, thereby increasing the concentrations of its substrate(s). The term “MGL-modulated” is used to refer to the condition of being affected by the modulation of the MGL enzyme including the condition of being affected by the inhibition of the MGL enzyme. The disclosure is directed to methods for treating, ameliorating and/or preventing autism spectrum disorder or symptoms thereof by the administration of therapeutically effective amounts of MGL modulators to subjects in need thereof.

The term “modulators” include both inhibitors and activators, where “inhibitors” refer to compounds that decrease, prevent, inactivate, desensitize, or down-regulate the MGL expression or activity, and “activators” are compounds that increase, activate, facilitate, sensitize, or up-regulate MGL expression or activity.

As used herein, unless otherwise noted, the term “affect” or “affected” (when referring to a disease, condition or disorder that is affected by inhibition of MGL) includes a reduction in the frequency and/or severity of one or more symptoms or manifestations of the disease, condition or disorder; and/or include the prevention of the development of one or more symptoms or manifestations of said disease, condition or disorder or the development of the disease, condition or disorder.

In treatment methods according to the invention, a therapeutically effective amount of at least one azabicycle compound as described herein is administered to a subject suffering from or diagnosed as having ASD. A “therapeutically effective amount” means an amount or dose sufficient to generally bring about the desired therapeutic or prophylactic benefit in subjects in need of such treatment for ASD. Effective amounts or doses of the active agents of the present invention may be ascertained by routine methods such as modeling, dose escalation studies or clinical trials, and by taking into consideration routine factors, e.g., the mode or route of administration or drug delivery, the pharmacokinetics of the agent, the severity and course of the disease, disorder, or condition, the subject's previous or ongoing therapy, the subject's health status and response to drugs, and the judgment of the treating physician. For a 70-kg human, an illustrative range for a suitable dosage amount is from about 1 to 1000 mg/day, or 1 to 500 mg/day, or 10 to 400 mg/day in single or multiple dosage units (e.g., BID, TID, QID or as required by modality). For a subject under the age of 18, suitable dosage amounts are from about 1 to 500 mg/day, or 5 to 40 mg/day in single or multiple dosage units (e.g., BID, TID, QID or as required by modality).

Once improvement of the subject's ASD has occurred, the dose may be adjusted for maintenance treatment or prevention, e.g., of symptom recurrence. For example, the dosage or the frequency of administration, or both, may be reduced as a function of the symptoms, to a level at which the desired therapeutic or prophylactic effect is maintained. Of course, if symptoms have been alleviated to an appropriate level, treatment may cease. Subjects may, however, require intermittent treatment on a long-term basis upon any recurrence of symptoms.

In addition, the azabicycle compounds described herein are envisaged for use alone, in combination with one or more additional azabicycle compounds as described herein, or in combination with additional active ingredients in the treatment of ASD. Additional active ingredients include but are not limited to agents used to treat ASD (e.g., approved or used off-label). In some embodiments, the additional active agent is selected from antipsychotics approved by FDA for treatment of irritability in autistic disorder (including aripiprazole and risperidone). Further additional active ingredients include treatments for comorbid attention deficit-hyperactivity disorder (ADHD) such as stimulants (such as dexamphetamine or methylphenidate salts) and non-stimulants such as those prescribed for hyperactivity, inattention, or impulsivity, or SSRIs/SNRIs for mood symptoms such as depression or anxiety symptoms, or sleep disorders (such as melatonin and derivatives thereof, e.g., Circadin). The additional active ingredients may be co-administered together or separately with the one or more azabicycle compounds or can be included with such an agent in a single pharmaceutical composition as described herein. In an illustrative embodiment, additional active ingredients are those that are known or discovered to be effective in the treatment of ASD or symptoms thereof. The combination may serve to increase efficacy (e.g., by including in the combination a compound potentiating the potency or effectiveness of an azabicycle compound as described herein), decrease one or more side effects, decrease the required dose of the active agent according to the invention, or affect other symptoms of ASD.

When referring to inhibiting the target, an “effective amount” means an amount sufficient to affect MGL modulation.

The azabicycle compounds described herein are envisaged for use, alone or in combination with one or more additional active ingredients, in pharmaceutical compositions of the invention. A pharmaceutical composition of the invention comprises a therapeutically effective amount of at least one azabicycle compound as described herein.

Pharmaceutically acceptable excipients commonly used in pharmaceutical compositions are substances that are non-toxic, biologically tolerable, and otherwise biologically suitable for administration to a subject, such as an inert substance, added to a pharmacological composition or otherwise used as a vehicle, carrier, or diluent to facilitate administration of an agent and that is compatible therewith. Examples of such excipients include calcium carbonate, calcium phosphate, various sugars and types of starch, cellulose derivatives, gelatin, vegetable oils, and polyethylene glycols.

Delivery forms of the pharmaceutical compositions containing one or more dosage units of the active agents may be prepared using pharmaceutically acceptable excipients and compounding techniques known or that become available to those of ordinary skill in the art. The compositions may be administered in the inventive methods by a suitable route of delivery, e.g., oral, parenteral, rectal, topical, or ocular routes, or by inhalation.

The preparation may be in the form of tablets, capsules, sachets, dragees, powders, granules, lozenges, powders for reconstitution, liquid preparations, or suppositories. The compositions may be formulated for any one of a plurality of administration routes, such as intravenous infusion, topical administration, or oral administration. Preferably, the compositions may be formulated for oral administration.

For oral administration, the active agents of the invention can be provided in the form of tablets or capsules, or as a solution, emulsion, or suspension. To prepare the oral compositions, the active agents may be formulated to yield a dosage of, e.g., for a 70-kg human, an illustrative range for a suitable dosage amount is from about 1 to 1000 mg/day in single or multiple dosage units. For adults or subjects under the age of 18, an illustrative range for suitable daily dosage amount is as described herein. In some embodiments, bodyweight-based dosing may be considered for boys and girls, as treatments for ASD may be expected to be used in school-aged children. For example, boys aged 8 years have an expected 50th percentile weight of −25 kg, and boys aged 12 years have an expected 50th percentile weight of −40 kg. It may be determined that different doses may be required for safe and efficacious treatment in younger children as compared with adolescents and adults.

Oral tablets may include the active ingredient(s) mixed with compatible pharmaceutically acceptable excipients such as diluents, disintegrating agents, binding agents, lubricating agents, sweetening agents, flavoring agents, coloring agents and preservative agents. Suitable inert fillers include sodium and calcium carbonate, sodium and calcium phosphate, lactose, starch, sugar, glucose, methyl cellulose, magnesium stearate, mannitol, sorbitol, and the like. Exemplary liquid oral excipients include ethanol, glycerol, water, and the like. Starch, polyvinyl-pyrrolidone (PVP), sodium starch glycolate, microcrystalline cellulose, and alginic acid are exemplary disintegrating agents. Binding agents may include starch and gelatin. The lubricating agent, if present, may be magnesium stearate, stearic acid or talc. If desired, the tablets may be coated with a material such as glyceryl monostearate or glyceryl distearate to delay absorption in the gastrointestinal tract or may be coated with an enteric coating.

Capsules for oral administration include hard and soft gelatin or (hydroxypropyl)methyl cellulose capsules. To prepare hard gelatin capsules, active ingredient(s) may be mixed with a solid, semi-solid, or liquid diluent. Liquids for oral administration may be in the form of suspensions, solutions, emulsions or syrups or may be lyophilized or presented as a dry product for reconstitution with water or other suitable vehicle before use. Such liquid compositions may optionally contain: pharmaceutically-acceptable excipients such as suspending agents (for example, sorbitol, methyl cellulose, sodium alginate, gelatin, hydroxyethyl cellulose, carboxymethylcellulose, aluminum stearate gel and the like); non-aqueous vehicles, e.g., oil (for example, almond oil or fractionated coconut oil), propylene glycol, ethyl alcohol, or water; preservatives (for example, methyl or propyl p-hydroxybenzoate or sorbic acid); wetting agents such as lecithin; and, if desired, flavoring or coloring agents.

The active agents of this invention may also be administered by non-oral routes. For example, compositions may be formulated for rectal administration as a suppository, enema or foam. For parenteral use, including intravenous, intramuscular, intraperitoneal, or subcutaneous routes, the agents of the invention may be provided in sterile aqueous solutions or suspensions, buffered to an appropriate pH and isotonicity or in parenterally acceptable oil. Suitable aqueous vehicles include Ringer's solution and isotonic sodium chloride. Such forms may be presented in unit-dose form such as ampules or disposable injection devices, in multi-dose forms such as vials from which the appropriate dose may be withdrawn, or in a solid form or pre-concentrate that can be used to prepare an injectable formulation. Illustrative infusion doses range from about 1 to 1000 μg/kg/minute of agent admixed with a pharmaceutical carrier over a period ranging from several minutes to several days.

For topical administration, the agents may be mixed with a pharmaceutical carrier at a concentration of about 0.01% to about 20% of drug to vehicle, preferably 0.1% to 10%. Another mode of administering the agents of the invention may utilize a patch formulation to affect transdermal delivery.

Active agents may alternatively be administered in methods of this invention by inhalation, via the nasal or oral routes, e.g., in a spray formulation also containing a suitable carrier.

In a further embodiment, the invention is directed to a method of treating a subject suffering from or diagnosed with a disease, disorder, or condition associated with MGL modulation, comprising administering to the subject in need of such treatment a therapeutically effective amount of the active agent.

The compounds of Formula (I) are useful in methods for treating, ameliorating and/or preventing ASD. Such methods comprise administering to a subject, such as an animal, a mammal, or a human, in need of such treatment, amelioration and/or prevention, a therapeutically effective amount of a compound of Formula (I), or an enantiomer, diastereomer, solvate or pharmaceutically acceptable salt thereof. In some embodiments, the subject is a human. In some embodiments, the subject is 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, or 2 years of age or younger. In some embodiments the subject is 18 years of age or older.

In particular, the compounds of Formula (I), or pharmaceutically acceptable salts, isotopes, N-oxides, solvates and stereoisomers thereof, are useful for treating, ameliorating and/or preventing ASD. More particularly, the compounds of Formula (I), or pharmaceutically acceptable salts, isotopes, N-oxides, solvates and stereoisomers thereof, are useful for treating, ameliorating and/or preventing ASD, autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS), Asperger's syndrome, Fragile X syndrome, Rett syndrome, childhood disintegrative disorder, Kanner's syndrome, Phelan McDermid Syndrome, Angelman syndrome, SCN2a related autism, SYNGAP related autism, Dub15q related autism, Dyrk1a related autism, GRIN2B related autism, Malan syndrome, ADNP syndrome, or tuberous sclerosis by administering to a subject in need thereof a therapeutically effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt, isotope, N-oxide, solvate or stereoisomer thereof as herein defined.

Embodiments of the azabicycle compounds for use as described herein are compounds of Formula (I):

wherein

-   X is CH₂ or O; -   Y is

-   R¹ is H; -   R^(2a) and R^(2b) are each independently H; -   R³ is 2,3-dihydro-1H-indene; pyridyl substituted with C₁₋₆alkyl;     phenyl; or phenyl substituted with one or two members each     independently selected from the group consisting of: halo,     C₁₋₆alkyl, C₁₋₆alkyl substituted with OH, C₁₋₆alkyl substituted with     CO₂H, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, O-phenyl, and     C₃₋₆cycloalkyl substituted with CH₃; -   R^(a) and R^(b) are each independently H or halo; and -   R^(c) is H or CH₃;     or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or     stereoisomer thereof.

In some embodiments of Formula (I), X is CH₂. In some embodiments, X is O.

In some embodiments, Y is

In some embodiments, Y is

In some embodiments, Y is

In some embodiments of Formula (I), R^(a) and R^(b) are both H. In some embodiments, R^(a) and R^(b) are each independently H or Cl. In some embodiments, R^(a) and R^(b) are both F.

In some embodiments, R³ is

In some embodiments, R³ phenyl, or phenyl substituted with one or two members each independently selected from the group consisting of: Cl, F, CH₃, CH₂CH₃, CH(CH₃)₂, C(CH₃)₃, CH₂CH(CH₃)₂, C(CH₃)₂CH₂OH, C(CH₃)₂CH₂CO₂H, CF₃, OCF₃, cyclopropyl, cyclopropyl substituted with CH₃, and O-phenyl. In some embodiments, R³ is

In some embodiments, R³ is 3-tert-butylphenyl, 4-tert-butylphenyl, 4-methyl-3-trifluoromethylphenyl, or 3,4-dimethylphenyl.

In some embodiments, the compound of Formula (I) is a compound as shown below in Table 1.

TABLE 1 Ex # Compound Name 1 (rac)-(2s,4s)-2-(1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 2 (2s,4*R)-2-((1*S,5*R)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 3 (2s,4*S)-2-((1*R,5*S)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 4 (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 5 (rac)-(2s,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 6 (rac)-(2s,4s)-2-(1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 7 (2s,4*S)-2-((1*R,5*S)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 8 (2s,4*R)-2-((1*S,5*R)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 9 (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 10 (2s,4*S)-2-((1*R,5*S)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 11 (2s,4*R)-2-((1*S,5*R)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 12 (rac)-(2r,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5- azaspiro[3.4]octan-6-one; 13 (rac)-(2r,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5- azaspiro[3.4]octan-6-one; 14 (2r,4*S)-2-((1*R,5*S)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 5-azaspiro[3.4]octan-6-one; 15 (2r,4*R)-2-((1*S,5*R)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 5-azaspiro[3.4]octan-6-one; 16 (rac)-(2s,4s)-2-(1-(3-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 17 (rac)-(2s,4s)-2-(1-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 18 (rac)-(2s,4s)-2-(1-(4-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 19 (rac)-(2s,4s)-2-(1-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 20 (rac)-(2s,4s)-2-(1-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 21 (rac)-(2s,4s)-2-(1-(m-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 22 (rac)-(2s,4s)-2-(1-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 23 (rac)-(2s,4s)-2-(1-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 24 (rac)-(2s,4s)-2-(1-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 25 (rac)-(2s,4s)-2-(1-(4-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 26 (rac)-(2s,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 27 (rac)-(2r,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 28 (rac)-(2s,4s)-2-(1-(4-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 29 (rac)-(2s,4s)-2-(1-(3-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 30 (rac)-(2s,4s)-2-(1-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 31 (rac)-(2s,4s)-2-(1-(3-(l-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 32 (rac)-(2s,4s)-2-(1-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 33 (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 34 (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 35 (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 36 (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 37 (rac)-(2s,4s)-2-(1-(3-Fluoro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 38 (2s,4S)-2-((1R,5S,6S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 39 (rac)-(2s,4s)-2-(6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 40 (2s,4S)-2-((1R,6S)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 41 (2s,4R)-2-((1S,6R)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 42 (rac)-(2s,4s)-2-(7,7-Difluoro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 43 (rac)-(2s,4s)-2-(6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 44 (2s,4*R)-2-((1*S,6*R)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 45 (2s,4*S)-2-((1*R,6*S)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 46 (rac)-(2s,4s)-2-(6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 47 (2s,4*R)-2-((1*S,6*R)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 48 (2s,4*S)-2-((1*R,6*S)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 49 (rac)-(2s,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 50 (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 51 (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 52 (rac)-(2r,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 53 (rac)-(2s,4s)-2-(6-(o-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 54 (rac)-(2s,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 55 (rac)-(2r,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 56 (rac)-(2s,4s)-2-(6-(p-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 57 (rac)-(2s,4s)-2-(6-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 58 (rac)-(2s,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 59 (rac)-(2r,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)- 5-azaspiro[3.4]octan-6-one; 60 (rac)-(2s,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 61 (rac)-(2r,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5- azaspiro[3.4]octan-6-one; 62 (rac)-(2s,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 63 (rac)-(2r,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5- azaspiro[3.4]octan-6-one; 64 (rac)-(2s,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 65 (rac)-(2r,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5- azaspiro[3.4]octan-6-one; 66 (rac)-(2s,4s)-2-(6-(4-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 67 (rac)-(2s,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 68 (rac)-(2r,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)- 5-azaspiro[3.4]octan-6-one; 69 (rac)-(2s,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 70 (rac)-(2r,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 71 (rac)-(2s,4s)-2-(6-(3-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 72 (rac)-(2s,4s)-2-(6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 73 (rac)-(2s,4s)-2-(6-(3-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 74 (rac)-(2s,4s)-2-(6-(4-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 75 (rac)-(2s,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane- 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 76 (rac)-(2r,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 77 (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 78 (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 79 (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 5-azaspiro[3.4]octan-6-one; 80 (2s,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 81 (2r,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 82 (2s,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 83 (2r,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 5-azaspiro[3.4]octan-6-one; 84 (2s,4S)-2-((1R,5S,6S)-6-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 85 (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethyl)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 86 (2s,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 87 (2r,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5- azaspiro[3.4]octan-6-one; 88 (2s,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 7-oxa-5-azaspiro[3.4]octan-6-one; 89 (2r,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 5-azaspiro[3.4]octan-6-one; 90 (2s,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 91 (2r,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5- azaspiro[3.4]octan-6-one; 92 (2s,4S)-2-((1R,5S,6S)-6-(2,3-Dihydro-1H-inden-5-yl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; and 93 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 94 (rac)-(25,45)-2-(1-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 95 (2r,4*S)-2-((1*R,5*S)-1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 96 (2r,4*R)-2-((1*S,5*R)-l-(4-(l-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 97 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 98 (2s,4S)-2-((1R,5S,6S)-6-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 99 (2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(ter/-Butyl)phenyl)-1-methyl-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 100 (2s,4*R)-2-((1*S,5*R,6*S)-6-(3-(ter/-Butyl)phenyl)-1-methyl-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 101 (2s,4S)-2-((1R,5S,6S)-6-(3-Isobutylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- oxa-5-azaspiro[3.4]octan-6-one; 102 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3,4-Dimethylphenyl)-1-methyl-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 103 (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl-5-D)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 104 (2s,4S)-2-((1R,5S,6S)-6-(3-(1-Hydroxy-2-methylpropan-2-yl)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 105 2-Methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carbonyl)-3- azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoic acid; 106 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(3-(trifluoromethyl)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 107 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-(trifluoromethoxy)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 108 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(4-Cyclopropylphenyl)-1-methyl-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 109 (2s,4S)-2-((1R,5S,6S)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 110 (2s,4S)-2-((1R,5S,6S)-6-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 111 (2s,4S)-2-((1R,5S,6S)-6-(3-Ethyl-4-fluorophenyl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 112 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethyl)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 113 (2s,4S)-2-((1R,5S,6S)-6-(2-Methyl-3-(trifluoromethyl)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 114 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 115 (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3- azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 116 (2s,4S)-2-((1R,5S,6R)-6-(6-(terl-Butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 117 (2s,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 118 (2s,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 119 (2r,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 120 (2r,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 121 (2r,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 122 (2r,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3- carbonyl)-5-azaspiro[3.4]octan-6-one; 123 (rac)-(2s,4s)-2-(7-Chloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; and 124 (rac)-(2s,4s)-2-(7,7-Dichloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; and pharmaceutically acceptable salts, isotopes, N-oxides, solvates, and stereoisomers thereof.

In some embodiments, the azabicycle compound is selected from the group consisting of:

-   (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; -   (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; -   (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; -   (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one;     and -   (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one;     and pharmaceutically acceptable salts, isotopes, N-oxides, solvates,     and stereoisomers thereof.

In some embodiments, the azabicycle compound is (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof. In some embodiments, the azabicycle compound is (2s,4*R)-2-((1*S,5*R)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one, or a pharmaceutically acceptable salt thereof. In some embodiments, the azabicycle compound is (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one, or a pharmaceutically acceptable salt, isotope, N-oxides, solvate, or stereoisomer thereof. In some embodiments, the azabicycle compound is (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one, or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof. In some embodiments, the azabicycle compound is (2s,4S)-2-((1R,5S,6S)-6-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one, or a pharmaceutically acceptable salt thereof. In some embodiments, the azabicycle compound is (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one, or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof. In some embodiments, the azabicycle compound is (2s,4*S)-2-((1*R,6*S)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one, or a pharmaceutically acceptable salt thereof. In some embodiments, the azabicycle compound is (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one, or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof.

In some embodiments, the azabicycle compound is a compound of Formula (IA):

wherein

-   X is CH₂ or O; and -   R³ is phenyl; or phenyl substituted with one or two members each     independently selected from the group consisting of: halo,     C₁₋₆alkyl, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, O-phenyl,     and C₃₋₆cycloalkyl substituted with CH₃;     or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or     stereoisomer thereof.

In some embodiments, the azabicycle compound is a compound of Formula (IB):

wherein

-   X is CH₂ or O; -   R³ is 2,3-dihydro-1H-indene; pyridyl substituted with C₁₋₆alkyl; or     phenyl substituted with one or two members each independently     selected from the group consisting of: halo, C₁₋₆alkyl, C₁₋₆alkyl     substituted with OH, C₁₋₆alkyl substituted with CO₂H, C₁₋₆haloalkyl,     OC₁₋₆haloalkyl and cyclopropyl; and -   R^(c) is H or CH₃;     or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or     stereoisomer thereof.

In some embodiments, the azabicycle compound is a compound of Formula (IC):

wherein

-   X is CH₂ or O; -   R³ is phenyl; or phenyl substituted with one or two members each     independently selected from the group consisting of: halo,     C₁₋₆alkyl, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, and     C₃₋₆cycloalkyl substituted with CH₃; and -   R^(a) and R^(b) are each independently selected from the group     consisting of: H, Cl and F;     or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or     stereoisomer thereof.

An additional embodiment of the invention is a method of treating ASD or a symptom thereof comprising administering an effective amount of a pharmaceutical composition, or use of a pharmaceutical composition for treating ASD, or a pharmaceutical composition for such use, comprising:

-   -   (A) at least one compound selected from compounds of Formula (I)

wherein

-   X is CH₂ or O; -   Y is

-   R¹ is H; -   R^(2a) and R^(2b) are each H; -   R³ is 2,3-dihydro-1H-indene; pyridyl substituted with C₁₋₆alkyl;     phenyl; or phenyl substituted with one or two members each     independently selected from the group consisting of: halo,     C₁₋₆alkyl, C₁₋₆alkyl substituted with OH, C₁₋₆alkyl substituted with     CO₂H, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, O-phenyl, and     C₃₋₆cycloalkyl substituted with CH₃; -   R^(a) and R^(b) are each independently H or halo; and -   R^(c) is H or CH₃;     and pharmaceutically acceptable salts, isotopes, N-oxides, solvates,     and stereoisomers of compounds of Formula (I);     -   and (B) at least one pharmaceutically acceptable excipient.

In some embodiments, such pharmaceutical compositions comprise a therapeutically effective amount of at least one compound in Table 1, or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof, or a pharmaceutically acceptable prodrug of at least one compound of Table 1, or at least one pharmaceutically active metabolite of Table 1; and at least one pharmaceutically acceptable excipient.

In some embodiments, the pharmaceutical composition comprises a therapeutically effective amount of at least one compound of Formula (IA), or a pharmaceutically acceptable salt, N-oxide or solvate, pharmaceutically acceptable prodrug, or pharmaceutically active metabolite of Formula (IA); and at least one pharmaceutically acceptable excipient.

In some embodiments, the pharmaceutical composition comprises a therapeutically effective amount of at least one compound of Formula (IB), or a pharmaceutically acceptable salt, N-oxide or solvate, pharmaceutically acceptable prodrug, or pharmaceutically active metabolite of Formula (IB); and at least one pharmaceutically acceptable excipient.

In some embodiments, the pharmaceutical composition comprises a therapeutically effective amount of at least one compound of Formula (IC), or a pharmaceutically acceptable salt, N-oxide or solvate, pharmaceutically acceptable prodrug, or pharmaceutically active metabolite of Formula (IC); and at least one pharmaceutically acceptable excipient.

In some embodiments, the azabicycle compounds are enantiomers and diastereomers of the compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)), pharmaceutically acceptable salts, N-oxides or solvates of the compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)), pharmaceutically acceptable prodrugs of compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)), and pharmaceutically active metabolites of the compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)).

In some embodiments, the azabicycle compounds are isotopic variations of compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)), such as, e.g., deuterated compounds of Formula (I), pharmaceutically acceptable salts, N-oxides or solvates of the isotopic variations of the compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)), pharmaceutically acceptable prodrugs of the isotopic variations of the compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)), and pharmaceutically active metabolites of the isotopic variations of the compounds of Formula (I) (as well as Formulas (IA), (IB), and (IC)).

Exemplary compounds useful in methods of the invention will now be described by reference to the illustrative synthetic schemes for their general preparation below and the specific examples that follow. Artisans will recognize that, to obtain the various compounds herein, starting materials may be suitably selected so that the ultimately desired substituents will be carried through the reaction scheme with or without protection as appropriate to yield the desired product. Alternatively, it may be necessary or desirable to employ, in the place of the ultimately desired substituent, a suitable group that may be carried through the reaction scheme and replaced as appropriate with the desired substituent. Unless otherwise specified, the variables are as defined above in reference to Formula (I). Reactions may be performed between the melting point and the reflux temperature of the solvent, and preferably between 0° C. and the reflux temperature of the solvent. Reactions may be heated employing conventional heating or microwave heating. Reactions may also be conducted in sealed pressure vessels above the normal reflux temperature of the solvent.

Abbreviations and acronyms used herein include the following:

TABLE 2 Term Acronym Bis(triphenylphosphine)palladium(II) dichloride PdCl₂(PPh₃)2 Microliter uL or uL Acetonitrile ACN, MeCN Aqueous aq Atmosphere atm tert-Butyloxycarbonyl BOC or Boc Benzotriazol-1-yloxy- BOP tris(dimethylamino)phosphonium hexafluorophosphate Broad br Mesylate[(di(1-adamantyl)-n-butylphosphine)-2-(2'- CatacXium ® amino-1,1'-biphenyl)]palladium(II) A Pd G3 Diatomaceous Earth Celite ® 1,8-Diazabicyclo[5.4.0]undec-7-ene DBU N,N‘-Dicyclohexylcarbodiimide DCC Dichloromethane DCM Diisobutylaluminum hydride DIBAL-H Diisopropyl ether DIPE N-Ethyldiisopropylamine DIPEA 4-Dimethylaminopyridine DMAP 1,2-Dimethoxy ethane DME Dimethylformamide DMF Dimethylsulfoxide DMSO 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide EDC, ED AC or EDCI Electrospray ionization ESI Diethyl ether Ether, Et₂O Ethyl Acetate EtOAc, or EA Ethanol EtOH Normal-phase silica gel chromatography FCC Grams g Hours h, hr, hrs 1-[Bis(dimethylamino)methylene]-1H-1,2,3- HATU triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate N, N, N', N'-Tetramethyl-O-(1H--benzotriazol-1- HBTU yl)uronium hexafluorophosphate Hydroxybenzotri azole HOBt High-pressure liquid chromatography HPLC Hertz Hz Isopropyl alcohol iPrOH, IPA Potassium tert-butoxide KOtBu Lithium aluminum hydride LAH Liquid chromatography and mass spectrometry LCMS Molar M Mass to charge ratio m/z Methanol MeOH Milligrams mg Minute min Milliliter mL Millimoles mmol Mass spectrometry MS Normal N Sodium acetate NaOAc N-Bromosuccinimide NBS Nuclear magnetic resonance NMR Palladium on carbon Pd/C Bis(dibenzylideneacetone)palladium Pd(dba)2 Bis(diphenylphosphino)ferrocene]dichloropalladium(II) Pd(dppf)Cl₂ Tetrakis(triphenylphosphine)palladium Pd(PPh₃)₄ Parts per million ppm Protecting Group PG Precipitate ppt Poly tetrafluoroethyl ene PTFE Bromotripyrrolidinophosphonium hexafluorophosphate PyBroP ® Reverse Phase RP Retention time R_(t) Room temperature rt Saturated sat Supercritical Fluid Chromatography SFC 2-Dicyclohexylphosphino-2’,6’-dimethoxybiphenyl SPhos Temperature T 2,4,6-Tripropyl-l,3,5,2,4,6-trioxatriphosphorinane- T3P ® 2,4,6-trioxide Triethylamine TEA Trifluoroacetic acid TFA Trifluoroacetic anhydride TFAA Tetrahydrofuran THF Thin layer chromatography TLC N,N,N’,N’-T etram ethylethylenediamine TMEDA Volume in milliliters of solvent per gram of substrate V, or volumes

PREPARATIVE EXAMPLES

Exemplary compounds useful in methods of the invention will now be described by reference to the illustrative synthetic schemes for their general preparation below and the specific examples to follow.

According to SCHEME 1, a compound of formula (V), where R^(a) is C₁₋₄alkyl, is treated with hydroxylamine; using an additive such as sodium acetate (NaOAc), and the like; in a suitable solvent such as ethanol (EtOH), and the like; to provide a compound of formula (VI). A compound of formula (VII) is prepared from a compound of formula (VI) using an oxidant such as hydrogen peroxide, urea-hydrogen peroxide, and the like; in the presence of an activator such as trifluoroacetic anhydride (TFAA), and the like; in the presence of a base such as dibasic sodium phosphate, and the like; in a solvent such as acetonitrile (ACN), and the like.

According to SCHEME 2, compounds of formula (VIIIa) and (VIIIb) are prepared by reacting a compound of formula (VII), where R^(a) is C₁₋₄alkyl, with formaldehyde in the presence of a base such as triethylamine (TEA), and the like; in a solvent such as ACN, and the like. A compound of formula (IX) is prepared by hydrogenolysis of a compound of formula (VIIIb) under an atmosphere of hydrogen gas (H₂) in the presence of a catalyst such as palladium on carbon (Pd/C), and the like; in a solvent such as ethyl acetate (EtOAc), EtOH, and the like. A compound of formula (X) is prepared by the reaction of a compound of formula (IX) with triphosgene in the presence of a base such as TEA, and the like; in a solvent such as tetrahydrofuran (THF), and the like. A compound of formula (XI) is prepared by the acidic deprotection of a compound of formula (X) using an acid such as trifluoroacetic acid (TFA), HCl in dioxane, and the like.

According to SCHEME 3, compounds of formula (XIIa) and formula (XIIb) are prepared by a Michael-type reaction between a compound of formula (VII), where R^(a) is ethyl; and methyl acrylate; in the presence of a base such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and the like; in a solvent such as ACN, and the like. Reductive ring closure of a compound of formula (XIIa) using a reducing agent such as sodium borohydride (NaBH₄), and the like; an additive such as nickel(II) chloride hexahydrate, and the like; in a suitable solvent such as methanol (MeOH), and the like; provides a compound of formula (XIII), where X is CH₂.

According to SCHEME 4, a compound of formula (XIV) may be prepared by reacting a compound of formula (VII), where R^(a) is C₁₋₄alkyl; with acetaldehyde in the presence of a base such as TEA, and the like; in a solvent such as ACN, and the like, at temperatures ranging from 0° C. to room temperature, for a period of 18 h. A compound of formula (XIV) may be subjected to hydrogenolysis; employing conditions previously described, to provide compounds of formula (XVa) and (XVb).

According to SCHEME 5, a compound of formula (XVa), where R^(a) is C₁₋₄alkyl, may be subjected to ring closure conditions with triphosgene, employing conditions previously described, to provide a compound of formula (XVI). A compound of formula (XVI) may be subjected to acidic deprotection conditions previously described to provide a compound of formula (XVII), where X is O.

According to SCHEME 6, a commercially available or synthetically accessible compound of formula (XVIII), is reacted in a Simmons-Smith type reaction to provide a compound of formula (XIX). For example, compound of formula (XVIII), where PG is BOC, and n is independently 1 or 2, is reacted with diethylzinc; diiodomethane; and TFA; in a suitable solvent such as dichloromethane (DCM), and the like; at temperatures ranging from −40° C. to −15° C. The BOC protecting group is cleaved under these conditions. Boc protection is achieved employing di-tert-butyl dicarbonate; a suitable base such as TEA, and the like; and 4-dimethylaminopyridine (DMAP); in a suitable solvent such as THF, DCM, and the like; to provide a compound of formula (XIX). A compound of formula (XIX) is treated with potassium bifluoride (KHF₂) in a suitable solvent such as MeOH, and the like; at temperatures ranging from rt to the reflux temperature of the solvent; to provide a compound of formula (XX).

According to SCHEME 7, a compound of formula (XX), where n is independently 1 or 2, and PG is BOC, is reacted with a variably substituted bromobenzene of formula (XXI), where R³ is a suitably substituted aryl group; a catalyst such as mesylate[(di(1-adamantyl)-n-butylphosphine)-2-(2′-amino-1,1′-biphenyl)]palladium(II) (CatacXium® A Pd G3), and the like; a base such as cesium carbonate (Cs₂CO₃), and the like; in a mixture of solvents such as toluene/water, and the like; at a temperature range of 80° C. to 100° C.; for a period of 18 h; to provide a compound of formula (XXII). Cleavage of the protecting group on a compound of formula (XXII) is achieved according to procedures known to one skilled in the art. For example, acidic conditions such as TFA/DCM, HCl/Dioxane, and the like, provides a compound of formula (XXIII).

According to SCHEME 8, tert-butyl 3-methyl-2,5-dihydro-1H-pyrrole-1-carboxylate is deprotected employing conditions previously described to provide 3-methyl-2,5-dihydro-1H-pyrrole. 3-Methyl-2,5-dihydro-1H-pyrrole undergoes reductive amination with benzaldehyde using a reducing agent such as sodium triacetoxyborohydride, sodium cyanoborohydride, and the like; in a suitable solvent such as DCM, and the like; to afford 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole.

According to SCHEME 9, a compound of formula (XXIV), where R³ is suitably substituted aryl group, is condensed with 4-methylbenzenesulfonhydrazide; in a suitable solvent such as THF, MeOH, and the like; at room temperature for a period of 1-16 h to provide a compound of formula (XXV). A compound of formula (XXV) is treated with a base such as sodium hydride (NaH), sodium hydroxide, and the like; with or without an additive such as benzyltriethylammonium chloride; in a solvent such as THF, toluene, and the like; at temperatures ranging from room temperature to 80° C.; for a period of 1-2 h; and the resulting aryldiazo intermediate is reacted under the Charette modification of Simmons-Smith cyclopropanation conditions with a compound of formula (XXVI), where R^(c) is H or CH₃; with a suitable catalyst such as zinc diiodide, and the like; in a solvent such as DCM, and the like; at room temperature; over 1-16 h; to provide a compound of formula (XXVII). A compound of formula (XXVIII) is prepared by hydrogenolysis of a compound of formula (XXVII) under an atmosphere of H₂; in the presence of a catalyst such as Pd/C, and the like; in a suitable solvent such as EtOAc, EtOH, MeOH, THF, and the like. Alternatively, a compound of formula (XXVIII) is prepared by deprotecting a compound of formula (XXVII) using an acylating agent such as 1-chloroethylcarbonochloridate; a base such as TEA, and the like; in a solvent such as DCM, and the like; followed by stirring in a solvent such as MeOH and the like; at a temperature of 80° C.

According to SCHEME 10, a compound of formula (XXIV), where R³ is suitably substituted aryl group, is condensed with hydrazine monohydrate; at room temperature for a period of 30 min; to provide a compound of formula (XXIX). A compound of formula (XXIX) is treated with manganese(IV) oxide; in a suitable solvent such as 1,4-dioxane, and the like; at room temperature; for a period of 2 h; and the resulting intermediate is reacted with N-benzylmaleimide at a temperature of 100° C. for a period of 16 h to provide a compound of formula (XXXI). Under conditions known to one skilled in the art, a compound of formula (XXXI) is reduced with a reducing agent such as NaBH₄, LiAlH₄, LiBH₄, diisobutylaluminum hydride (DIBAL-H), and the like; in a suitable solvent such as THF, MeOH, EtOH, and the like; at temperatures ranging from −78 to 0° C.; for a period of 30 min to 16 h; to provide a compound of formula (XXVII), where R^(c) is H. A compound of formula (XXVII) is subjected to hydrogenolysis employing conditions previously described to provide a compound of formula (XXVIII).

According to SCHEME 11, pinacol(dichloromethyl)boronate is reacted with sodium iodide (NaI); in a suitable solvent such as acetone, and the like; at a temperature of 55° C. over a period of 72 h to provide pinacol(diiodomethyl)boronate. Either pinacol(diiodomethyl)boronate or pinacol(dichloromethyl)boronate is reacted with a pre-stirred mixture of chromium(II) chloride; N,N,N′,N′-tetramethylethylenediamine (TMEDA); in a suitable solvent such as THF, and the like; before adding tert-butyl 2,5 dihydro-1H-pyrrole-1-carboxylate and heating to 50° C. for 20 h to provide tert-butyl (1R,5S,6s)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate. tert-Butyl (1R,5S,6s)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate is reacted under Suzuki coupling conditions with a suitably substituted aryl halide of formula (XXXII), where R³ is a suitably substituted aryl group and X is either iodo or bromo; a palladium catalyst such as bis(triphenylphosphine)palladium(II) dichloride, CataCXium A Pd G3, and the like; a suitable base such a potassium phosphate, Cs₂CO₃, and the like; in a suitable solvent such as dioxane, water, EtOH, or a mixture thereof, to provide a compound of formula (XXXIV). A compound of formula (XXXIV) is submitted to deprotection conditions as previously described to a compound of formula (XXVIII), where R^(c) is H.

According to SCHEME 12, a compound of Formula (I), where R¹ is hydrogen and X is CH₂ or O, is prepared by conventional amide bond forming techniques such as coupling reactions which are well known to those skilled in the art (such as HATU (1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate), BOP (benzotriazol-1-yloxy-tris(dimethylamino)phosphonium hexafluorophosphate), or conversion of the acid to an acid chloride). For example, reaction of a compound of formula (XXVIII), where R^(c) is H or CH₃, and R³ is as defined in claim 1; or a compound of formula (XXIII), where n is each independently 1 or 2; is reacted with a synthetically accessible suitably substituted carboxylic acid of formula (XXXV) (which includes a compound of formula (XI)), where the acid is activated with an appropriate activating reagent, for example a carbodiimide, such as N,N′-dicyclohexylcarbodiimide (DCC) or 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC, EDAC or EDCI) optionally in the presence of hydroxybenzotriazole (HOBt) and/or a catalyst such as 4-dimethylaminopyridine (DMAP); a halotrisaminophosphonium salt such as (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), or bromotripyrrolidinophosphonium hexafluorophosphate (PyBroP®); a suitable pyridinium salt such as 2-chloro-1-methyl pyridinium chloride; or another suitable coupling agent such as N,N,N′,N′-tetramethyl-O-(1H-benzotriazol-1-yl)uronium hexafluorophosphate (HBTU), 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxid hexafluorophosphate (HATU), 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide (T3P®) and the like. Coupling reactions are conducted in a suitable solvent such as DCM, THF, DMF and the like, optionally in the presence of a tertiary amine such as N-methylmorpholine, N-ethyldiisopropylamine (DIPEA), or triethylamine (TEA), at a temperature ranging from 0° C. to rt, to provide a compound of Formula (I).

A compound of Formula (I) where R³ is phenyl substituted with C(CH₃)₂CO₂CH₃ is reacted under hydrolysis conditions known to one skilled in the art, for example, utilizing a base such as LiOH.H₂O, and the like; in a suitable solvent such as water, 1,4-dioxane, and the like; at room temperature for up to 16 hours to provide a compound of Formula (I) where R³ is phenyl substituted with C(CH₃)₂CO₂H.

A compound of Formula (I), where Y is

where R^(c) is H, and R³ is phenyl substituted with I and tert-butyl, is reacted in an H-Cube® under continuous-flow deuteration conditions utilizing D₂O as the source for deuterium gas; a suitable catalyst such as Pd/C and the like; in a suitable solvent such as CD₃OD, tetrahydrofuran-d₈, or a mixture thereof; to provide (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-butyl)phenyl-5-D)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one.

According to SCHEME 13, a suitably substituted, commercially available aryl bromide of formula (XXXVI), where R³ is phenyl substituted with one or two members each independently selected from F or C₁₋₄alkyl; is reacted with a base, such as n-BuLi, and the like; a formyl source such as DMF and the like; in a solvent such as THF, and the like; for a period of 3 hours at a temperature of −70° C. to provide a compound of formula (XXIV).

A compound of formula (XXIV), where R³ is phenyl substituted with one or two members each independently selected from Br or C₁₋₄alkyl; is reacted in a metal-mediated cross coupling reaction to provide a compound of formula (XXIV), where R³ is phenyl substituted with one or two members each independently selected from C₃₋₆cycloalkyl or C₁₋₄alkyl. For example, a compound of formula (XXIV), where R³ is substituted with Br and CH₃; is reacted with a commercially available suitably substituted boronic acid such as cyclopropylboronic acid; in the presence of a palladium catalyst such as Pd(OAc)₂, bis(triphenylphosphine)palladium(II)chloride (PdCl₂(PPh₃)₂), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (PdCl₂(dppf)), tetrakis(triphenylphosphine)palladium(0) (Pd(PPh₃)₄), 2-dicyclohexylphosphino-2′,6′-diisopropoxy-1,1′-biphenyl)[2-(2′-amino-1,1′-biphenyl)]palladium(II) methanesulfonate (RuPhos-Pd-G3), and the like; a phosphine ligand such as PPh₃; base such as potassium phosphate, Na₂CO₃, Cs₂CO₃, and the like; in a suitable solvent such as ACN, water, 1,4-dioxane, toluene, or a mixture thereof; at a temperature ranging from 70° C.-120° C.; for a period ranging from 2 h to 48 h, using conventional or microwave heating, to provide a compound of formula (XXIV), where R³ is phenyl substituted with cyclopropyl and CH₃.

According to SCHEME 14, 1-iodo-3-methyl-benzene is treated with tert-butyl chloride and aluminum chloride; for a period of 1 h; at temperatures ranging from 0° C. to rt; to provide 1-tert-butyl-3-iodo-5-methylbenzene. 1-tert-Butyl-3-iodo-5-methylbenzene is treated with (PhCO₂)₂; and NBS; in a suitable solvent such as carbon tetrachloride; at reflux temperature; for a period of 16 hours; to provide 1-(bromomethyl)-3-tert-butyl-5-iodobenzene. 1-(Bromomethyl)-3-tert-butyl-5-iodobenzene is oxidized under Kornblum conditions; in a suitable solvent such as DMSO, and the like; at temperatures ranging from rt to 100° C.; to provide a compound of formula (XXIV) where R³ is phenyl substituted with iodo and tert-butyl.

According to SCHEME 15, (1R,5S,6s)-3-benzyl-6-(3-bromophenyl)-3-azabicyclo[3.1.0]hexane is reacted with ((1-methoxy-2-methylprop-1-en-1-yl)oxy)trimethylsilane; ZnF₂; a suitable catalyst such as Pd₂(dba)₃, and the like; and a ligand such as P(t-Bu)₃, and the like; at a temperature of 90° C. over 6 hours to provide a compound of formula (XXVII), where R^(c) is H and R³ is phenyl substituted with C(CH₃)₂CO₂CH₃. A compound of formula (XXVIII), where R³ is phenyl substituted with C(CH₃)₂CO₂CH₃ is prepared from a compound of formula (XXVII), where R^(c) is H and R³ is phenyl substituted with C(CH₃)₂CO₂CH₃ employing hydrogenolysis conditions known to one skilled in the art or as previously described.

A compound of formula (XXVIII), where R^(c) is H and R³ is phenyl substituted with C(CH₃)₂CH₂OH, is prepared in two steps from a compound of formula (XXVII), where R^(c) is H and R³ is phenyl substituted with C(CH₃)₂CO₂CH₃. In a first step, a compound of formula (XXVII), where R^(c) is H and R³ is phenyl substituted with C(CH₃)₂CO₂CH₃ is reduced employing conditions known to one skilled in the art. For example, a compound of formula (XXVII), where R^(c) is H and R³ is phenyl substituted with C(CH₃)₂CO₂CH₃ is reduced with a suitable reducing agent such as NaBH₄, LiAlH₄, LiBH₄, diisobutylaluminum hydride (DIBAL-H), and the like; in a suitable solvent such as tetrahydrofuran (THF), methanol (MeOH), ethanol (EtOH), and the like; at temperatures ranging from −78 to 0° C.; for a period of 30 min to 16 h. Subsequent hydrogenolysis, employing conditions as previously described, to provides a compound of formula (XXVIII), where R^(c) is H and R³ is phenyl substituted with C(CH₃)₂CH₂OH.

Alternately, (racemic)-(1*R,5*S,6*R)-3-benzyl-6-(4-bromo-3-(trifluoromethoxy)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane is reacted in a metal-mediated cross coupling reaction with a commercially available suitably substituted borane, such as 2,4,6-trimethyl-1,3,5,2,4,6-trioxatriborinane; in the presence of a palladium catalyst such as Pd(OAc)₂, bis(triphenylphosphine)palladium(II)chloride (PdCl₂(PPh₃)₂), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (PdCl₂(dppf)), tetrakis(triphenylphosphine)palladium(0) (Pd(PPh₃)₄), 2-dicyclohexylphosphino-2′,6′-diisopropoxy-1,1′-biphenyl)[2-(2′-amino-1,1′-biphenyl)]palladium(II) methanesulfonate (RuPhos-Pd-G3), and the like; a phosphine ligand such as PPh₃; base such as potassium phosphate, Na₂CO₃, Cs₂CO₃, and the like; in a suitable solvent such as ACN, water, 1,4-dioxane, toluene, or a mixture thereof, at a temperature ranging from 70° C.-120° C.; for a period ranging from 2 h to 48 h, using conventional or microwave heating, to provide a compound of formula (XXVII), where R³ is phenyl substituted with OCF₃ and CH₃. A compound of formula (XXVII), where R³ is phenyl substituted with OCF₃ and CH₃, is reacted under hydrogenolysis conditions as previously described, to provide a compound of formula (XXVIII), where R^(c) is H.

According to SCHEME 16, a compound of formula (XXIX), where R³ is as described in claim 1, is treated with tert-butyl 2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carboxylate, employing conditions previously described in SCHEME 10, to provide a compound of formula (XXXIV). A compound of formula (XXVIII), is prepared in two steps from a compound of formula (XXXIV). In a first step, deprotection of the tert-butyl carbamate protecting group is achieved employing conditions known to one skilled in the art, or as previously described. Subsequent reduction of is achieved employing conditions known to one skilled in the art, for example, reduction with a suitable reducing agent such as NaBH₄, LiAlH₄, LiBH₄, diisobutylaluminum hydride (DIBAL-H), and the like; with an additive such as BF₃.OEt₂; in a suitable solvent such as THF, MeOH, EtOH, and the like; at temperatures ranging from 0 to 50° C.; for a period of 30 min to 16 h; to provide a compound of formula (XXVIII), where R^(c) is H.

Compounds of Formula (I) may be converted to their corresponding salts using methods known to one of ordinary skill in the art. For example, an amine of Formula (I) is treated with trifluoroacetic acid, HCl, or citric acid in a solvent such as Et₂O, CH₂C₁₂, THF, MeOH, chloroform, or isopropanol to provide the corresponding salt form. Alternately, trifluoroacetic acid or formic acid salts are obtained as a result of reverse phase HPLC purification conditions. Crystalline forms of pharmaceutically acceptable salts of compounds of Formula (I) may be obtained in crystalline form by recrystallization from polar solvents (including mixtures of polar solvents and aqueous mixtures of polar solvents) or from non-polar solvents (including mixtures of non-polar solvents).

Where the compounds according to this invention have at least one chiral center, they may accordingly exist as enantiomers. Where the compounds possess two or more chiral centers, they may additionally exist as diastereomers. It is to be understood that all such isomers and mixtures thereof are encompassed within the scope of the present invention.

Compounds prepared according to the schemes described above may be obtained as single forms, such as single enantiomers, by form-specific synthesis, or by resolution. Compounds prepared according to the schemes above may alternately be obtained as mixtures of various forms, such as racemic (1:1) or non-racemic (not 1:1) mixtures. Where racemic and non-racemic mixtures of enantiomers are obtained, single enantiomers may be isolated using conventional separation methods known to one of ordinary skill in the art, such as chiral chromatography, recrystallization, diastereomeric salt formation, derivatization into diastereomeric adducts, biotransformation, or enzymatic transformation. Where regioisomeric or diastereomeric mixtures are obtained, as applicable, single isomers may be separated using conventional methods such as chromatography or crystallization.

The following specific examples are provided to further illustrate the invention and various preferred embodiments.

EXAMPLES

In obtaining the compounds described in the examples below and the corresponding analytical data, the following experimental and analytical protocols were followed unless otherwise indicated.

Unless otherwise stated, reaction mixtures were magnetically stirred at room temperature (rt) under a nitrogen atmosphere. Where solutions were “dried,” they were generally dried over a drying agent such as Na₂SO₄ or MgSO₄. Where mixtures, solutions, and extracts were “concentrated”, they were typically concentrated on a rotary evaporator under reduced pressure. Reactions under microwave irradiation conditions were carried out in a Biotage Initiator or CEM (Microwave Reactor) Discover instrument.

For the reactions conducted under continuous flow conditions, “flowed through a LTF-VS mixer” refers to the use of a Chemyx Fusion 100 Touch Syringe Pump that is in line via 1/16″ PTFE tubing to a LTF-VS mixer (Little Things Factory GmbH (http://www.ltf-gmbh.com), unless otherwise indicated.

Normal-phase silica gel chromatography (FCC) was performed on silica gel (SiO₂) using prepacked cartridges.

Preparative reverse-phase high performance liquid chromatography (RP HPLC) was performed on either:

METHOD A. An Agilent HPLC with an Xterra Prep RP18 column (5 μM, 30×100 or 50×150 mm) or an XBridge C18 OBD column (5 μM, 30×100 or 50×150 mm), and a mobile phase of 5% ACN in 20 mM NH₄OH was held for 2 min, then a gradient of 5-99% ACN over 15 min, then held at 99% ACN for 5 min, with a flow rate of 40 or 80 mL/min.

or

METHOD B. A Shimadzu LC-8A Series HPLC with an Inertsil ODS-3 column (3 μm, 30×100 mm, T=45° C.), mobile phase of 5% ACN in H₂O (both with 0.05% TFA) was held for 1 min, then a gradient of 5-99% ACN over 6 min, then held at 99% ACN for 3 min, with a flow rate of 80 mL/min.

or

METHOD C. A Shimadzu LC-8A Series HPLC with an XBridge C18 OBD column (5 μm, 50×100 mm), mobile phase of 5% ACN in H₂O (both with 0.05% TFA) was held for 1 min, then a gradient of 5-99% ACN over 14 min, then held at 99% ACN for 10 min, with a flow rate of 80 mL/min.

or

METHOD D. A Gilson HPLC with an XBridge C18 column (5 μm, 100×50 mm), mobile phase of 5-99% ACN in 20 mM NH₄OH over 10 min and then hold at 99 ACN for 2 min, at a flow rate of 80 mL/min.

or

METHOD E. An ACCQ Prep HPLC with an XBridge C18 OBD column (5 μM, 50×100), mobile phase of 5% ACN in H₂O (both with 0.05% TFA) was held for 1 min, then a gradient of 5-95% ACN over 12 min, then held at 95% ACN for 2 min, with a flow rate of 80 mL/min.

Preparative supercritical fluid high performance liquid chromatography (SFC) was performed on either on a Jasco preparative SFC system, an APS 1010 system from Berger instruments, or a SFC-PICLAB-PREP 200 (PIC SOLUTION, Avignon, France). The separations were conducted at 100 to 150 bar with a flow rate ranging from 40 to 60 mL/min. The column was heated to 35 to 40° C.

SFC Method: SFC-Lux Cellulose-1, Column Phenomenex Lux Cellulose-1 150×4.6 mm, 5 μm, Isocratic mode: 40% Methanol+0.1% Diethylamine and 60% CO₂)

Mass spectra (MS) were obtained on an Agilent series 1100 MSD using electrospray ionization (ESI) in positive mode unless otherwise indicated. Calculated (calcd.) mass corresponds to the exact mass.

Nuclear magnetic resonance (NMR) spectra were obtained on Bruker model DRX spectrometers. Definitions for multiplicity are as follows: s=singlet, d=doublet, t=triplet, q=quartet, p=pentet, hept=heptet, dd=doublet of doublets, dt=doublet of triplets, dq=double of quartets, dp=doublet of pentets, td=triplet of doublets, tt=triplet of triplets, ddd=doublet of doublet of doublets, m=multiplet, br=broad. It will be understood that for compounds comprising an exchangeable proton, said proton may or may not be visible on an NMR spectrum depending on the choice of solvent used for running the NMR spectrum and the concentration of the compound in the solution.

Chemical names were generated using ChemDraw Ultra 17.1 (CambridgeSoft Corp., Cambridge, Mass.) or OEMetaChem V1.4.0.4 (Open Eye).

Compounds designated as *R or *S are enantiopure compounds where the absolute configuration was not determined.

Intermediate 1: tert-Butyl 3-nitrocyclobutanecarboxylate

Step A: tert-Butyl 3-hydroxyiminocyclobutanecarboxylate. To a solution of tert-butyl 3-oxocyclobutane-1-carboxylate (100 g, 588 mmol) in ethanol (EtOH) (1.8 L) was added sodium acetate (NaOAc) (192 g, 2340 mmol) and hydroxylamine hydrochloride (81 g, 1166 mmol). The reaction mixture was stirred at reflux for 4 h then filtered through a pad of Celite® and the pad was washed with EtOH. The combined filtrates were evaporated and the residue was taken up in ethyl acetate (EtOAc) and washed with water and brine. The organic layer was dried over magnesium sulfate, filtered, and concentrated to give the title compound (108 g, 584 mmol, 99%) as a white solid. MS (ESI): mass calcd. for C₉H₁₅NO₃ 185.1; m/z found, 186.2 [M+H]⁺.

Step B: tert-Butyl 3-nitrocyclobutanecarboxylate. To a suspension of urea hydrogen peroxide (164 g, 1.74 mol) in acetonitrile (MeCN) (1 L) was added a solution of trifluoroacetic anhydride (TFAA) (245 mL, 1.75 mol) in MeCN (500 mL) dropwise over 1 h at −10° C. The reaction mixture was stirred at room temperature for 1 h. The solution was added to a solution of tert-butyl 3-hydroxyiminocyclobutanecarboxylate (108 g, 0.584 mol) and sodium phosphate dibasic (911 g, 6.42 mol) in MeCN (1 L) dropwise over 30 min at 80° C. The reaction mixture was stirred at 80° C. for 30 min then filtered through a pad of Celite® and the pad was washed with MeCN. The combined filtrates were diluted with EtOAc. The mixture was washed with water and brine. The organic layer was dried over magnesium sulfate, filtered and evaporated. The residue was purified by flash column chromatography (FCC) on silica (0-20% EtOAc in heptane) to give the title compound (89.6 g, 445 mmol, 76%) as a yellow oil as a 1.3:1 mixture of cis/trans isomers. Compound does not ionize with ESI⁺ LCMS.

Intermediate 2: Ethyl 3-nitrocyclobutanecarboxylate

The title compound was prepared in a manner analogous to Intermediate 1 using ethyl 3-oxocyclobutane-1-carboxylate instead of tert-butyl 3-oxocyclobutane-1-carboxylate in Step A. Compound does not ionize with ESI⁺ LCMS. ¹H NMR (300 MHz, Chloroform-d) δ 5.02-4.70 (m, 1H), 4.20 (q, J=7.2 Hz, 2H), 3.04-2.71 (m, 5H), 1.29 (t, J=7.0 Hz, 3H).

Intermediate 3: (2s,4s)-6-Oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid

Step A: tert-Butyl (1s,3s)-3-(hydroxymethyl)-3-nitrocyclobutane-1-carboxylate. To a solution of tert-butyl 3-nitrocyclobutanecarboxylate (Intermediate 1, 89.6 g, 445 mmol) in MeCN (1 L) was added formaldehyde (37 wt % in water, 73 mL, 971 mmol). To the reaction mixture was added triethylamine (TEA) (62 mL, 444 mmol) dropwise at 0° C. and the reaction was stirred at room temperature for 2 h. The reaction mixture was evaporated and the residue was purified by FCC on silica (0-25% EtOAc in heptane) to give the title compound (38.25 g, 165 mmol, 37%) as a white powder. MS (ESI): mass calcd. for C₁₀H₁₇NO₅ 231.2; m/z found, 254.1 [M+Na]⁺. trans-tert-Butyl 3-(hydroxymethyl)-3-nitro-cyclobutanecarboxylate was formed, but not isolated.

Step B: tert-Butyl (1s,3s)-3-amino-3-(hydroxymethyl)cyclobutane-1-carboxylate. To a solution of tert-butyl (1s,3s)-3-(hydroxymethyl)-3-nitro-cyclobutanecarboxylate (38.2 g, 165 mmol) in EtOAc (600 mL) was added 10% palladium on carbon (Pd/C) (1.9 g). The reaction mixture was stirred at 50° C. for 1 h under hydrogen (H₂) (10 bar). The reaction mixture was filtered through a pad of Celite®. To the filtrate was added 10% Pd/C (1.9 g). The reaction mixture was stirred at 50° C. for 2 h under H₂ (10 bar). The reaction mixture was filtered through a pad of Celite® and the Celite® was washed with EtOAc. The combined filtrates were evaporated and the residue was triturated with diethyl ether (Et₂O) to give the title compound (18.6 g, 92.4 mmol, 55%) as a white powder. MS (ESI): mass calcd. for C₁₀H₁₉NO₃ 201.1; m/z found, 202.2 [M+H]⁺. ¹H NMR (300 MHz, DMSO-d₆) δ 5.26-3.98 (m, 1H), 3.74-2.94 (m, 4H), 2.70-2.57 (m, 1H), 2.20-2.07 (m, 2H), 1.97-1.82 (m, 2H), 1.39 (s, 9H).

Step C: tert-Butyl (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylate. To a solution of tert-butyl (1s,3s)-3-amino-3-(hydroxymethyl)cyclobutane-1-carboxylate (18.6 g, 92.4 mmol) in tetrahydrofuran (THF) (300 mL) was added TEA (26 mL, 186 mmol). To the mixture was added a solution of triphosgene (9.6 g, 32.4 mmol) in THF (200 mL) dropwise at −10° C. and stirred at room temperature for 1 h. The reaction mixture poured into saturated sodium bicarbonate (600 mL) and the mixture was extracted with EtOAc. The combined organic layers were dried over magnesium sulfate, filtered, and evaporated. The residue was triturated with Et₂O to give the title compound (17.7 g, 77.9 mmol, 84%) as a white powder. MS (ESI): mass calcd. for C₁₁H₁₇NO₄ 227.1; m/z found, 228.2 [M+H]⁺.

Step D: (2s,4s)-6-Oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid. To trifluoroacetic acid (TFA) (180 mL, 235 mmol) was added tert-butyl (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylate (17.7 g, 77.9 mmol) in portions at 0° C. The reaction mixture was stirred at room temperature for 1 h. The reaction mixture was evaporated and the residue was triturated with Et₂O to afford the title compound (12.9 g, 75.4 mmol, 96%) as a white powder. MS (ESI): mass calcd. for C₇H₉NO₃ 171.0; m/z found, 172.1 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 12.26 (br s, 1H), 8.08 (s, 1H), 4.34 (s, 2H), 2.79-2.66 (m, 1H), 2.43-2.29 (m, 4H).

Intermediate 4: (2r,4s)-6-Oxo-5-azaspiro[3.4]octane-2-carboxylic acid

Step A: Ethyl (1r,3s)-3-(3-methoxy-3-oxopropyl)-3-nitrocyclobutane-1-carboxylate. To a solution of ethyl 3-nitrocyclobutanecarboxylate (Intermediate 2, 16.6 g, 95.6 mmol) in MeCN (145 mL) was added methyl acrylate (10.3 mL, 114 mmol). To the reaction mixture was added 1,8-diazabicyclo[5.4.0]undec-7-ene (7.1 mL, 47.6 mmol) dropwise at 0° C. and the reaction mixture was stirred at 0° C. for 1 h. The reaction mixture was diluted with saturated ammonium chloride and EtOAc and the layers were separated. The organic layer was dried over magnesium sulfate, filtered and evaporated. The residue was purified by FCC on silica (0-15% EtOAc in heptane) to give the title compound (13.6 g, 52.7 mmol, 55%) as a colorless liquid. MS (ESI): mass calcd. for C₁₁H₁₇NO₆ 259.1; m/z found, 282.1 [M+Na]⁺. ¹H NMR (300 MHz, Chloroform-d) δ 4.17 (q, J=7.1 Hz, 2H), 3.70 (s, 3H), 3.12-2.79 (m, 3H), 2.69-2.49 (m, 2H), 2.48-2.21 (m, 4H), 1.27 (t, J=7.1 Hz, 3H).

Step B: (2r,4s)-6-Oxo-5-azaspiro[3.4]octane-2-carboxylic acid. To a solution of ethyl (1r,3s)-3-(3-methoxy-3-oxopropyl)-3-nitrocyclobutane-1-carboxylate (13.6 g, 52.5 mmol) in methanol (MeOH) (133 mL) was added nickel(II) chloride hexahydrate (12.5 g, 52.6 mmol). To the reaction mixture was added sodium borohydride (NaBH₄) (10 g, 264 mmol) in small portions at −10° C. and the reaction mixture was stirred at 0° C. for 1 h. To the reaction mixture was added aqueous potassium carbonate (47 mL, 141 mmol, 3 M) dropwise at 0° C. (pH 10) and the reaction mixture was stirred at 0° C. for 1 h. The reaction mixture was filtered through a pad of Celite® and the pad was washed with EtOH. The combined filtrates were evaporated. The residue was purified by FCC on silica eluting with chloroform:methanol:acetic acid (100:0:0→9:1:1) to give the title compound (4.8 g, 28.2 mmol, 53%) as an off-white powder. MS (ESI): mass calcd. for C₈H₁₁NO₃ 169.1; m/z found, 170.1 [M+H]⁺. ¹H NMR (300 MHz, DMSO-d₆) δ 7.97 (br s, 1H), 4.01-2.94 (m, 1H), 2.82-2.65 (m, 1H), 2.36-2.01 (m, 8H).

Intermediate 5: Potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate

Step A: tert-Butyl 1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate. In a flask under N₂ was placed anhydrous DCM (62 mL) followed by diethylzinc (68 mL, 1 M in hexanes, 68 mmol). The mixture was cooled to −40° C. and a solution of diiodomethane (11 mL, 135 mmol) in DCM (26 mL) was slowly added by addition funnel over 30 min. The reaction was then allowed to stir at −40° C. for 1 h. At −40° C., a solution of TFA (5.2 mL, 68 mmol) in DCM (26 mL) was slowly added over 20 min by addition funnel. The reaction was warmed to −15° C. and stirred for 1 h. A solution of tert-butyl 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (2.5 g, 8.5 mmol) in DCM (26 mL) was slowly added by addition funnel to the reaction mixture. The reaction was allowed to warm overnight with stirring. Over the course of the reaction, the BOC group is cleaved and must be reinstalled. After stirring overnight, the crude reaction mixture is partially concentrated to one quarter volume. THF (38 mL) is added followed by di-tert-butyl dicarbonate (9.2 g, 42 mmol), TEA (11.8 mL, 85 mmol), and DMAP (0.25 g, 2.1 mmol). The reaction was stirred at room temperature for 3 h under N₂, after which it was diluted with EtOAc and washed with sat. NaHCO₃. The organic layer was dried over MgSO₄, filtered, and concentrated under reduced pressure to afford the crude product as red-brown oil. The crude product was purified by FCC on silica (0-10% EtOAc in heptane). The desired fractions were collected and concentrated under vacuum to yield a pale yellow solid (1.0 g, 38% yield). MS (ESI): mass calcd. for C₁₆H₂₈BNO₄ 309.2; m/z found, 254.0 [M+2H−tBu]⁺. ¹H NMR (300 MHz, CDCl₃) δ 3.67-3.27 (m, 4H), 1.66-1.55 (m, 1H), 1.41 (s, 9H), 1.22 (s, 12H), 0.95 (dd, J=7.2, 4.1 Hz, 1H), 0.44-0.35 (m, 1H).

Step B: Potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate. tert-Butyl 1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate (1 g, 3.2 mmol) was dissolved in MeOH (20 mL), treated with KHF₂ (1.8 g, 22.6 mmol) and stirred at 65° C. for 16 h. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. The resulting residue was triturated with 20% Et₂O in heptane (13 mL) for 10 min. The precipitate was collected by filtration and rinsed with Et₂O. The precipitate was dissolved in hot ACN (100 mL) and filtered to remove KHF₂. The filtrate was collected and concentrated under reduced pressure to afford the title compound as a white solid (830 mg, 88% yield). MS (ESI): mass calcd. for C₁₀H₁₆BF₃KNO₂ 289.1; m/z found, 172.1 [M−tBu−KF]⁺. ¹H NMR (300 MHz, DMSO-d₆) δ 3.30 (s, 1H), 3.19-3.05 (m, 3H), 1.35 (s, 9H), 0.94 (s, 1H), 0.39-0.29 (m, 1H), −0.41 (s, 1H).

Intermediate 6: Potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate

The title compound was prepared in a manner analogous to Intermediate 5 using tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydropyridine-1(2H)-carboxylate instead of tert-butyl 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate in Step A. MS (ESI): mass calcd. for C₁₁H₁₈BF₃KNO₂ 303.1; m/z found, 186.0 [M−tBu−KF]⁺. ¹H NMR (300 MHz, DMSO-d₆) δ 3.51-3.36 (m, 2H), 3.11-3.02 (m, 1H), 2.89 (s, 1H), 1.81-1.69 (m, 1H), 1.36 (s, 9H), 1.31-1.21 (m, 1H), 0.63-0.53 (m, 1H), 0.26-0.16 (m, 1H), −0.29 (s, 1H).

Intermediate 7: Potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-1-yl)trifluoroborate

The title compound was prepared in a manner analogous to Intermediate 5 using tert-butyl 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydropyridine-1(2H)-carboxylate instead of tert-butyl 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate in Step A. MS (ESI): mass calcd. for C₁₁H₁₈BF₃KNO₂ 303.1; m/z found, 186.0 [M−tBu−KF]⁺. ¹H NMR (300 MHz, DMSO-d₆) δ 3.66-3.38 (m, 2H), 3.19 (s, 1H), 2.72 (s, 1H), 1.76-1.51 (m, 2H), 1.39-1.36 (m, 9H), 0.60 (s, 1H), 0.23-0.14 (m, 1H), −0.35 (s, 1H).

Intermediate 8: 4-Bromo-1-methyl-2-(trifluoromethoxy)benzene

4-Bromo-2-(trifluoromethoxy)iodobenzene (321 μL, 1.9 mmol) added to a solution of tetrakis(triphenylphosphine)palladium (220 mg, 0.19 mmol) in anhydrous THF (90 mL) under N₂. Dimethylzinc solution (1M in hexane, 2.86 mL) was added dropwise. The mixture was stirred at 50° C. for 3 h. The reaction mixture was partially concentrated under vacuum (product is volatile) and filtered through silica gel eluting with pentane. The result was partially concentrated to yield the title compound (486 mg, crude). This was used without further purification in subsequent steps. MS (ESI): mass calcd. for C₈H₆BrF₃O 254.0; m/z found, 253.9 [M]⁺. ¹H NMR (300 MHz, CDCl₃) δ 7.39-7.30 (m, 2H), 7.13 (d, J=8.1 Hz, 1H), 2.27 (s, 3H).

Intermediate 9: 1-Benzyl-3-methyl-2,5-dihydro-1H-pyrrole

To a solution of tert-butyl 3-methyl-2,5-dihydro-1H-pyrrole-1-carboxylate (250 mg, 1.36 mmol) in DCM (4 mL) was added TFA (1 mL), and the reaction stirred at room temperature for 40 min. The mixture was concentrated in vacuo, the residue re-dissolved in DCM (2.6 mL), and benzaldehyde (0.14 mL, 1.36 mmol) added. After stirring at room temperature for 1 h, sodium triacetoxyborohydride (578 mg, 2.73 mmol) was added portion-wise and the reaction allowed to stir overnight. The mixture was carefully quenched with sat. aq. NaHCO₃ and the aqueous phase extracted with DCM. The combined organic layers were washed with brine, dried over Na₂SO₄, filtered, and the filtrate concentrated under reduced pressure. The crude residue was purified by FCC on silica (0-10% of a 2M NH₃/MeOH solution in DCM) to afford the title compound as a brown oil (104 mg, 44%). MS (ESI): mass calcd. for C₁₂H₁₅N, 173.1; m/z found, 174.1 [M+H]⁺. ¹H NMR (600 MHz, Chloroform-d) δ 7.37-7.34 (m, 2H), 7.33-7.30 (m, 2H), 7.25 (d, J=10.2 Hz, 1H), 5.39-5.36 (m, J=1.8 Hz, 1H), 3.80 (s, 2H), 3.48-3.44 (m, 2H), 3.37-3.34 (m, 2H), 1.73-1.69 (m, 3H).

Intermediate 10: 3-Isobutylbenzaldehyde

n-BuLi (2.2 mL, 2.5 M in hexane, 5.5 mmol) was added dropwise to a −70° C. solution of 1-bromo-3-isobutylbenzene (1.0 g, 4.7 mmol) in anhydrous THF (15 mL). The resultant mixture was stirred at −70° C. for 1 hour before being treated with DMF (0.36 mL, 4.7 mmol). The mixture was stirred at −70° C. for 2 hours before being quenched with water and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to give the title compound (800 mg, crude), as a colorless oil. ¹H NMR (400 MHz, DMSO-d₆) δ 9.99 (s, 1H), 7.77-7.67 (m, 2H), 7.54-7.49 (m, 2H), 2.55 (d, J=7.3 Hz, 2H), 1.92-1.80 (m, 1H), 0.86 (d, J=6.5 Hz, 6H).

Intermediate 11: 3-Ethyl-4-fluorobenzaldehyde

The title compound was prepared in a manner analogous to Intermediate 10 using 4-bromo-2-ethyl-1-fluorobenzene instead of 1-bromo-3-isobutylbenzene. ¹H NMR (400 MHz, CDCl₃) δ 9.84-9.79 (m, 1H), 7.68-7.64 (m, 1H), 7.63-7.58 (m, 1H), 7.07-7.00 (m, 1H), 2.62 (q, J=7.5 Hz, 2H), 1.15 (t, J=7.6 Hz, 3H).

Intermediate 12: 4-Cyclopropyl-2-methylbenzaldehyde

4-Bromo-2-methylbenzaldehyde (1.5 g, 7.54 mmol) was taken up in 1,4-dioxane (15 mL) and water (6 mL) under a nitrogen atmosphere. To this was added cyclopropylboronic acid (1.6 g, 18.8 mmol), Cs₂CO₃ (5.4 g, 16.6 mmol), and Pd(dppf)Cl₂ (0.92 g, 1.13 mmol). The mixture was stirred at 90° C. for 16 h before cooling to rt. The mixture was filtered through Celite® then diluted with diethylether and washed with water and brine. The organic phase was dried over MgSO₄, filtered, and concentrated under reduced pressure. The crude product was purified by FCC (0-40% DCM in pentane) to provide the title compound as a colorless oil (1.2 g, 96% yield). ¹H NMR (300 MHz, CDCl₃) δ 10.18 (s, 1H), 7.68 (d, J=8.0 Hz, 1H), 7.00 (d, J=7.9 Hz, 1H), 6.92 (s, 1H), 2.63 (s, 3H), 2.00-1.82 (m, 1H), 1.05 (dd, J=7.2, 5.4 Hz, 2H), 0.89-0.67 (m, 2H).

Intermediate 13: 3-tert-Butyl-5-iodobenzaldehyde

Step A: 1-tert-Butyl-3-iodo-5-methylbenzene. tert-Butyl chloride (178 g, 1.93 mol) and 1-iodo-3-methyl-benzene (280 g, 1.28 mol) were placed under N₂ and cooled to 0° C. To this was added aluminum chloride (514 g, 3.85 mol) and the resulting solution was allowed to warm to rt and stirred for 1 h. The reaction was diluted with DCM and purified by FCC (0-2% EtOAc in ether) to provide the title compound as a colorless oil (202 g, 57% yield).

Step B: 1-(Bromomethyl)-3-tert-butyl-5-iodobenzene. 1-tert-Butyl-3-iodo-5-methylbenzene (202 g, 737 mmol), CCl₄ (3.0 L), and (PhCO₂)₂ (8.9 g, 36.8 mmol) were combined under N₂ and heated to reflux. To this was added NBS (262 g, 1.47 mol) and the resulting solution was heated at reflux overnight. The reaction mixture was cooled to room temperature, diluted with H₂O, and extracted with DCM. The combined organic layers were washed with sat. aq. NaHCO₃, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude residue was purified by FCC (0-2% EtOAc in ether) to provide the title compound as a yellow oil (220 g, 85% yield).

Step C: 3-tert-Butyl-5-iodobenzaldehyde. 1-(Bromomethyl)-3-tert-butyl-5-iodobenzene (220 g, 625 mmol) was taken up in DMSO (2.2 L) under N₂ and stirred for 4 h at 100° C. The reaction mixture was cooled to room temperature, quenched with water, and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude residue was purified by FCC (0-2% EtOAc in ether) to provide the title compound as a white solid (100 g, 56% yield). MS (ESI): mass calcd. for C₁₁H₁₃IO, 288.0; m/z found, 288.1 [M]⁺.

Example 1: (rac)-(2s,4s)-2-(1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane (20 mg, 0.115 mmol) and (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 20 mg, 0.115 mmol) were taken up in DMF (0.6 mL). DIPEA (60 μL, 0.346 mmol) and HATU (50 mg, 0.127 mmol) were added and the reaction was stirred at rt for 16 h. The reaction mixture was filtered through a PTFE filter with MeOH and purified via reverse phase HPLC (5-95% ACN in 20 mM NH₄OH in water) to afford the title compound (30 mg, 80% yield). MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.10 (qd, J=8.2, 3.5 Hz, 4H), 6.54 (d, J=22.4 Hz, 1H), 4.36 (d, J=4.2 Hz, 2H), 4.23-3.93 (m, 1H), 3.86-3.54 (m, 3H), 2.92-2.81 (m, 1H), 2.71-2.62 (m, 2H), 2.52-2.36 (m, 2H), 2.32 (d, J=4.9 Hz, 3H), 1.95-1.79 (m, 1H), 1.18-1.07 (m, 1H), 0.73 (dt, J=9.6, 4.7 Hz, 1H).

Example 2: (2s,4*R)-2-((1*S,5*R)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 1 (Stationary phase: Lux Cellulose 4, 5 μm 250×21 mm, Mobile phase: 50% MeOH, 50% CO₂). MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.15-7.10 (m, 2H), 7.12-7.05 (m, 2H), 6.27 (d, J=20.1 Hz, 1H), 4.35 (d, J=5.3 Hz, 2H), 4.23-3.93 (m, 1H), 3.85-3.55 (m, 3H), 2.93-2.83 (m, 1H), 2.69-2.59 (m, 2H), 2.54-2.41 (m, 2H), 2.33 (d, J=4.9 Hz, 3H), 1.92-1.83 (m, 1H), 1.16-1.09 (m, 1H), 0.73 (dt, J=11.9, 4.7 Hz, 1H).

Example 3: (2s,4*S)-2-((1*R,5*S)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 1 (Stationary phase: Lux Cellulose 4, 5 μm 250×21 mm, Mobile phase: 50% MeOH, 50% CO₂). MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.13 (dd, J=8.0, 4.2 Hz, 2H), 7.12-7.05 (m, 2H), 6.12 (d, J=15.9 Hz, 1H), 4.35 (d, J=5.4 Hz, 2H), 4.23-3.93 (m, 1H), 3.84-3.56 (m, 3H), 2.93-2.83 (m, 1H), 2.67-2.58 (m, 2H), 2.54-2.41 (m, 2H), 2.33 (d, J=4.2 Hz, 3H), 1.92-1.83 (m, 1H), 1.13 (q, J=5.8 Hz, 1H), 0.74 (dt, J=11.6, 4.7 Hz, 1H).

Example 4: (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 1 using 1-phenyl-3-azabicyclo[3.1.0]hexane hydrochloride instead of 1-(p-tolyl)-3-azabicyclo[3.1.0]hexane. MS (ESI): mass calcd. for C₁₈H₂₀N₂O₃, 312.1; m/z found, 313.0 [M+H]⁺. ¹H NMR (500 MHz, CD₃OD) δ 7.40-7.08 (m, 5H), 4.48 (m, 2H), 4.17-3.96 (m, 1H), 3.93-3.78 (m, 2H), 3.61-3.53 (m, 1H), 3.02 (m, 1H), 2.61-2.40 (m, 4H), 2.04-1.93 (m, 1H), 1.17-1.10 (m, 1H), 0.75 (m, 1H).

Example 5: (rac)-(2s,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: tert-Butyl 1-(4-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carboxylate. In a vial was combined potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5, 210 mg, 0.73 mmol), CatacXium® A Pd G3 (30 mg, 0.036 mmol), 1-bromo-4-(tert-butyl)benzene (250 μL, 1.4 mmol), Cs₂CO₃ (709.9 mg, 2.2 mmol), toluene (14 mL) and water (1.4 mL). The resulting mixture was degassed by bubbling N₂ through the solution for 10 min. The reaction was then heated to 90° C. for 18 h. Water was added and the mixture was extracted with EtOAc. The organic layers were dried over MgSO₄, filtered, and concentrated under reduced pressure. The crude product was purified by FCC on silica (0-10% EtOAc in heptane). The desired fractions were collected and concentrated under vacuum to yield a yellow oil (190 mg, 83% yield). MS (ESI): mass calcd. for C₂₀H₂₉NO₂, 315.2; m/z found, 260.0 [M+2H−tBu]⁺. ¹H NMR (300 MHz, CDCl₃) δ 7.33 (d, J=8.2 Hz, 2H), 7.11 (t, J=7.7 Hz, 2H), 4.04-3.80 (m, 1H), 3.77-3.44 (m, 3H), 1.82-1.74 (m, 1H), 1.46 (s, 9H), 1.31 (s, 9H), 1.12-1.04 (m, 1H), 0.86-0.79 (m, 1H).

Step B: 1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane. TFA (0.55 mL, 7.2 mmol) was added to a solution of tert-butyl 1-(4-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carboxylate (190 mg, 0.6 mmol) in DCM (5 mL) at 0° C. The reaction mixture was stirred at rt for 1 h. The reaction mixture was concentrated under vacuum. DCM was added and washed with saturated solution of Na₂CO₃. The organic layers were combined, dried over MgSO₄, filtered, and concentrated under vacuum to yield a yellow oil. The product was used as such in the next step without further purification (129 mg, 0.6 mmol, yield 99%, crude). MS (ESI): mass calcd. for C₁₅H₂₁N, 215.2; m/z found, 216.1 [M+H]⁺.

Step C: (rac)-(2s,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. HBTU (297 mg, 0.8 mmol) and DIPEA (0.262 mL, 1.5 mmol) were added to a solution of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 123 mg, 0.722 mmol) in anhydrous DMF (4 mL). The mixture was stirred for 10 min at room temperature, then a solution of 1-(4-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane (129 mg, 0.6 mmol) in DMF (1 mL) was added, and the reaction mixture was stirred at room temperature for additional 16 h. Saturated NaHCO₃ was added and the mixture was extracted with EtOAc. The organic layers were dried over MgSO₄, filtered and concentrated under reduced pressure. The crude product was purified by FCC on silica (0-30% (DCM/MeOH 20:1) in DCM). The desired fractions were collected and concentrated under vacuum. The resulting solid was triturated with pentane, diisopropyl ether (DIPE), and filtered to yield a beige solid (121.2 mg, 52% yield). MS (ESI): mass calcd. for C₂₂H₂₈N₂O₃, 368.2; m/z found, 369.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.34 (dd, J=8.5, 2.0 Hz, 2H), 7.12 (dd, J=8.3, 5.0 Hz, 2H), 6.16 (d, J=6.6 Hz, 1H), 4.36 (d, J=4.5 Hz, 2H), 4.23-3.93 (m, 1H), 3.85-3.56 (m, 3H), 2.94-2.83 (m, 1H), 2.68-2.58 (m, 2H), 2.56-2.42 (m, 2H), 1.96-1.83 (m, 1H), 1.31 (d, J=1.5 Hz, 9H), 1.19-1.13 (m, 1H), 0.78-0.69 (m, 1H).

Example 6: (rac)-(2s,4s)-2-(1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-isopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.26-7.21 (m, 1H), 7.11 (t, J=7.9 Hz, 1H), 7.06-6.95 (m, 2H), 6.18 (d, J=26.5 Hz, 1H), 4.36 (d, J=3.3 Hz, 2H), 4.25-3.94 (m, 1H), 3.87-3.57 (m, 3H), 2.95-2.81 (m, 2H), 2.70-2.59 (m, 2H), 2.57-2.40 (m, 2H), 1.98-1.87 (m, 1H), 1.25 (dd, J=6.9, 2.7 Hz, 6H), 1.20-1.14 (m, 1H), 0.81-0.72 (m, 1H).

Example 7: (2s,4*S)-2-((1*R,5*S)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 6 (Stationary phase: Whelk O1 SS, 5 μm 250×21 mm, Mobile phase: 20% MeOH with 0.2% TEA, 80% CO₂). MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.23 (dd, J=7.6, 6.5 Hz, 1H), 7.14-7.06 (m, 1H), 7.05-6.95 (m, 2H), 6.54 (d, J=45.5 Hz, 1H), 4.36 (d, J=4.1 Hz, 2H), 4.25-3.94 (m, 1H), 3.86-3.56 (m, 3H), 2.95-2.82 (m, 2H), 2.71-2.61 (m, 2H), 2.52-2.40 (m, 2H), 1.98-1.86 (m, 1H), 1.24 (dd, J=6.9, 4.2 Hz, 6H), 1.16 (dt, J=8.5, 4.4 Hz, 1H), 0.76 (dt, J=16.0, 4.8 Hz, 1H).

Example 8: (2s,4*R)-2-((1*S,5*R)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 6 (Stationary phase: Whelk O1 SS, 5 μm 250×21 mm, Mobile phase: 20% MeOH with 0.2% TEA, 80% CO₂). MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.23 (dd, J=7.6, 6.4 Hz, 1H), 7.13-7.07 (m, 1H), 7.05-6.95 (m, 2H), 6.51 (d, J=45.8 Hz, 1H), 4.36 (d, J=4.1 Hz, 2H), 4.25-3.94 (m, 1H), 3.87-3.57 (m, 3H), 2.93-2.82 (m, 2H), 2.71-2.61 (m, 2H), 2.52-2.41 (m, 2H), 1.97-1.84 (m, 1H), 1.24 (dd, J=6.8, 4.1 Hz, 6H), 1.18-1.13 (m, 1H), 0.76 (dt, J=15.9, 4.8 Hz, 1H).

Example 9: (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-isopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.21-7.16 (m, 2H), 7.14-7.09 (m, 2H), 6.13 (d, J=11.4 Hz, 1H), 4.35 (d, J=4.4 Hz, 2H), 4.24-3.92 (m, 1H), 3.86-3.55 (m, 3H), 2.94-2.83 (m, 2H), 2.68-2.60 (m, 2H), 2.54-2.41 (m, 2H), 1.96-1.83 (m, 1H), 1.24 (dd, J=6.9, 1.5 Hz, 6H), 1.19-1.12 (m, 1H), 0.77-0.69 (m, 1H).

Example 10: (2s,4*S)-2-((1*R,5*S)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 9 (Stationary phase: Whelk O1 SS, 5 μm 250×21 mm, Mobile phase: 15% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 85% CO₂). MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.3 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.21-7.15 (m, 2H), 7.15-7.08 (m, 2H), 6.36 (d, J=13.1 Hz, 1H), 4.36 (d, J=4.6 Hz, 2H), 4.24-3.92 (m, 1H), 3.85-3.56 (m, 3H), 2.95-2.82 (m, 2H), 2.69-2.59 (m, 2H), 2.53-2.40 (m, 2H), 1.94-1.84 (m, 1H), 1.23 (dd, J=6.9, 2.0 Hz, 6H), 1.15 (dq, J=8.7, 4.3 Hz, 1H), 0.74 (dt, J=10.8, 4.8 Hz, 1H).

Example 11: (2s,4*R)-2-((1*S,5*R)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 9 (Stationary phase: Whelk O1 SS, 5 μm 250×21 mm, Mobile phase: 15% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 85% CO₂). MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.3 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.18 (dd, J=8.3, 3.1 Hz, 2H), 7.15-7.08 (m, 2H), 6.54 (d, J=15.8 Hz, 1H), 4.36 (d, J=4.6 Hz, 2H), 4.24-3.92 (m, 1H), 3.85-3.55 (m, 3H), 2.95-2.82 (m, 2H), 2.71-2.60 (m, 2H), 2.53-2.40 (m, 2H), 1.94-1.84 (m, 1H), 1.23 (dd, J=6.9, 2.5 Hz, 6H), 1.15 (dt, J=9.2, 5.1 Hz, 1H), 0.74 (dt, J=11.0, 4.7 Hz, 1H).

Example 12: (rac)-(2r,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-isopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₂, 352.2; m/z found, 353.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.95 (s, 1H), 7.24-7.08 (m, 4H), 4.05-3.56 (m, 3H), 3.47-3.37 (m, 1H), 3.01-2.79 (m, 2H), 2.34-2.06 (m, 8H), 2.01-1.86 (m, 1H), 1.17 (dd, J=6.9, 1.1 Hz, 6H), 1.06-0.99 (m, 1H), 0.66 (t, J=4.1 Hz, 1H).

Example 13: (rac)-(2r,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₃H₃₀N₂O₂, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.34 (dd, J=8.3, 2.6 Hz, 2H), 7.16-7.09 (m, 2H), 6.11 (s, 1H), 4.25-3.89 (m, 1H), 3.88-3.46 (m, 3H), 2.98-2.84 (m, 1H), 2.60-2.47 (m, 2H), 2.44-2.32 (m, 4H), 2.30-2.18 (m, 2H), 1.95-1.82 (m, 1H), 1.31 (s, 9H), 1.18-1.09 (m, 1H), 0.77-0.69 (m, 1H).

Example 14: (2r,4*S)-2-((1*R,5*S)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 13 (Stationary phase: Whelk O1 SS, 5 μm 250×21 mm, Mobile phase: 15% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 85% CO₂). MS (ESI): mass calcd. for C₂₃H₃₀N₂O₂, 366.2; m/z found, 367.3 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.34 (dd, J=8.2, 3.5 Hz, 2H), 7.12 (t, J=8.8 Hz, 2H), 6.17 (s, 1H), 4.25-3.89 (m, 1H), 3.88-3.46 (m, 3H), 2.90 (t, J=7.7 Hz, 1H), 2.60-2.45 (m, 2H), 2.37 (d, J=10.3 Hz, 4H), 2.21 (q, J=7.1 Hz, 2H), 1.94-1.81 (m, 1H), 1.31 (d, J=1.9 Hz, 9H), 1.14 (dt, J=9.1, 5.0 Hz, 1H), 0.74 (dt, J=9.8, 4.6 Hz, 1H).

Example 15: (2r,4*R)-2-((1*S,5*R)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 13 (Stationary phase: Whelk O1 SS, 5 μm 250×21 mm, Mobile phase: 15% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 85% CO₂). MS (ESI): mass calcd. for C₂₃H₃₀N₂O₂, 366.2; m/z found, 367.3 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.34 (dd, J=8.3, 3.6 Hz, 2H), 7.12 (t, J=8.7 Hz, 2H), 6.28-6.17 (m, 1H), 4.25-3.89 (m, 1H), 3.88-3.50 (m, 3H), 2.89 (tt, J=8.9, 4.4 Hz, 1H), 2.52 (td, J=11.1, 10.6, 6.3 Hz, 2H), 2.37 (d, J=10.3 Hz, 4H), 2.27-2.14 (m, 2H), 1.94-1.81 (m, 1H), 1.31 (d, J=2.1 Hz, 9H), 1.14 (p, J=4.9 Hz, 1H), 0.74 (dt, J=10.0, 4.8 Hz, 1H).

Example 16: (rac)-(2s,4s)-2-(1-(3-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-cyclopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₁H₂₄N₂O₃, 352.2; m/z found, 353.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.23-7.17 (m, 1H), 6.99-6.94 (m, 1H), 6.94-6.89 (m, 2H), 5.96 (d, J=10.5 Hz, 1H), 4.36 (d, J=3.3 Hz, 2H), 4.25-3.89 (m, 1H), 3.84-3.55 (m, 3H), 2.94-2.83 (m, 1H), 2.71-2.56 (m, 2H), 2.55-2.42 (m, 2H), 1.96-1.84 (m, 2H), 1.18-1.15 (m, 1H), 1.00-0.92 (m, 2H), 0.78-0.72 (m, 1H), 0.71-0.65 (m, 2H).

Example 17: (rac)-(2s,4s)-2-(1-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-(tert-butyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₃, 368.2; m/z found, 369.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.31-7.27 (m, 1H), 7.26-7.23 (m, 1H), 7.21-7.18 (m, 1H), 7.04-6.95 (m, 1H), 5.93 (d, J=15.7 Hz, 1H), 4.36 (d, J=4.3 Hz, 2H), 4.25-3.89 (m, 1H), 3.88-3.58 (m, 3H), 2.96-2.83 (m, 1H), 2.69-2.57 (m, 2H), 2.57-2.42 (m, 2H), 2.00-1.86 (m, 1H), 1.32 (d, J=2.3 Hz, 9H), 1.20-1.14 (m, 1H), 0.80-0.72 (m, 1H).

Example 18: (rac)-(2s,4s)-2-(1-(4-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-cyclopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₁H₂₄N₂O₃, 352.2; m/z found, 353.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.11-7.05 (m, 2H), 7.05-7.01 (m, 2H), 5.89 (br s, 1H), 4.35 (d, J=4.5 Hz, 2H), 4.25-3.89 (m, 1H), 3.84-3.55 (m, 3H), 2.95-2.82 (m, 1H), 2.67-2.56 (m, 2H), 2.55-2.42 (m, 2H), 1.93-1.81 (m, 2H), 1.16-1.13 (m, 1H), 1.01-0.91 (m, 2H), 0.77-0.70 (m, 1H), 0.70-0.62 (m, 2H).

Example 19: (rac)-(2s,4s)-2-(1-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₁₉F₃N₂O₄, 396.1; m/z found, 397.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.35 (td, J=8.0, 3.2 Hz, 1H), 7.15-7.07 (m, 2H), 7.00 (d, J=13.0 Hz, 1H), 5.95 (d, J=7.4 Hz, 1H), 4.36 (d, J=1.6 Hz, 2H), 4.25-3.92 (m, 1H), 3.89-3.56 (m, 3H), 2.96-2.82 (m, 1H), 2.69-2.57 (m, 2H), 2.57-2.43 (m, 2H), 2.01-1.90 (m, 1H), 1.19 (t, J=7.1 Hz, 1H), 0.88-0.80 (m, 1H).

Example 20: (rac)-(2s,4s)-2-(1-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-2-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.24 (s, 1H), 7.21-7.12 (m, 3H), 5.89 (d, J=11.2 Hz, 1H), 4.34 (d, J=17.2 Hz, 2H), 4.15-3.94 (m, 1H), 3.87-3.63 (m, 2H), 3.50-3.31 (m, 1H), 2.96-2.77 (m, 1H), 2.71-2.42 (m, 4H), 2.39 (d, J=2.4 Hz, 3H), 1.87-1.79 (m, 1H), 1.20-1.06 (m, 1H), 0.75 (q, J=4.8 Hz, 1H).

Example 21: (rac)-(2s,4s)-2-(1-(m-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.21 (td, J=7.5, 3.0 Hz, 1H), 7.05 (t, J=7.0 Hz, 1H), 7.01-6.95 (m, 2H), 5.95 (d, J=7.6 Hz, 1H), 4.36 (d, J 3.0 Hz, 2H), 4.25-3.89 (m, 1H), 3.86-3.55 (m, 3H), 2.95-2.84 (m, 1H), 2.68-2.57 (m, 2H), 2.57-2.43 (m, 2H), 2.34 (d, J=2.4 Hz, 3H), 1.99-1.86 (m, 1H), 1.19-1.11 (m, 1H), 0.80-0.70 (m, 1H).

Example 22: (rac)-(2s,4s)-2-(1-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₁₉F₃N₂O₄, 396.1; m/z found, 397.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.24-7.14 (m, 4H), 6.09 (d, J=8.1 Hz, 1H), 4.36 (d, J=4.9 Hz, 2H), 4.25-3.89 (m, 1H), 3.85-3.55 (m, 3H), 2.95-2.82 (m, 1H), 2.70-2.58 (m, 2H), 2.57-2.43 (m, 2H), 2.00-1.84 (m, 1H), 1.19-1.15 (m, 1H), 0.84-0.78 (m, 1H).

Example 23: (rac)-(2s,4s)-2-(1-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-(trifluoromethyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₁₉F₃N₂O₃, 380.1; m/z found, 381.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.56-7.30 (m, 4H), 6.16 (d, J=5.4 Hz, 1H), 4.36 (d, J=1.9 Hz, 2H), 4.25-3.93 (m, 1H), 3.90-3.57 (m, 3H), 2.97-2.84 (m, 1H), 2.72-2.60 (m, 2H), 2.57-2.43 (m, 2H), 2.04-1.93 (m, 1H), 1.24-1.18 (m, 1H), 0.89-0.82 (m, 1H).

Example 24: (rac)-(2s,4s)-2-(1-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-(trifluoromethyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₁₉F₃N₂O₃, 380.1; m/z found, 381.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.57 (dd, J=8.2, 3.3 Hz, 2H), 7.32-7.26 (m, 2H), 6.21 (d, J=15.1 Hz, 1H), 4.36 (d, J=2.7 Hz, 2H), 4.28-3.95 (m, 1H), 3.91-3.57 (m, 3H), 2.98-2.83 (m, 1H), 2.74-2.57 (m, 2H), 2.55-2.41 (m, 2H), 2.08-1.94 (m, 1H), 1.25-1.15 (m, 1H), 0.92-0.82 (m, 1H).

Example 25: (rac)-(2s,4s)-2-(1-(4-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 5-bromo-2-methylbenzotrifluoride instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.1; m/z found, 395.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.40 (d, J=16.8 Hz, 1H), 7.26-7.21 (m, 2H), 5.98 (d, J=8.8 Hz, 1H), 4.36 (d, J=2.7 Hz, 2H), 4.25-3.92 (m, 1H), 3.89-3.54 (m, 3H), 2.93-2.84 (m, 1H), 2.68-2.58 (m, 2H), 2.56-2.41 (m, 5H), 1.99-1.87 (m, 1H), 1.16 (dd, J=8.1, 5.3 Hz, 1H), 0.83-0.76 (m, 1H).

Example 26: (rac)-(2s,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-(1-methylcyclopropyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₆N₂O₃, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.21 (dd, J=8.4, 2.1 Hz, 2H), 7.13-7.06 (m, 2H), 6.02 (d, J=7.9 Hz, 1H), 4.35 (d, J=4.5 Hz, 2H), 4.25-3.89 (m, 1H), 3.85-3.54 (m, 3H), 2.94-2.81 (m, 1H), 2.69-2.57 (m, 2H), 2.55-2.41 (m, 2H), 1.93-1.82 (m, 1H), 1.39 (s, 3H), 1.18-1.13 (m, 1H), 0.83 (t, J=5.1 Hz, 2H), 0.78-0.70 (m, 3H).

Example 27: (rac)-(2r,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-(1-methylcyclopropyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₃H₂₈N₂O₂, 364.2; m/z found, 365.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.23-7.17 (m, 2H), 7.13-7.07 (m, 2H), 6.13 (s, 1H), 4.25-3.89 (m, 1H), 3.85-3.52 (m, 3H), 2.95-2.83 (m, 1H), 2.58-2.45 (m, 2H), 2.45-2.31 (m, 4H), 2.26-2.15 (m, 2H), 1.92-1.81 (m, 1H), 1.39 (d, J=1.6 Hz, 3H), 1.18-1.07 (m, 1H), 0.83 (t, J=5.1 Hz, 2H), 0.78-0.67 (m, 3H).

Example 28: (rac)-(2s,4s)-2-(1-(4-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 4-bromodiphenyl ether instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₄H₂₄N₂O₄, 404.2; m/z found, 405.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.36-7.30 (m, 2H), 7.19-7.07 (m, 3H), 7.02-6.93 (m, 4H), 5.99 (s, 1H), 4.35 (d, J=5.1 Hz, 2H), 4.25-3.89 (m, 1H), 3.86-3.56 (m, 3H), 2.92-2.83 (m, 1H), 2.69-2.58 (m, 2H), 2.56-2.41 (m, 2H), 1.93-1.83 (m, 1H), 1.19-1.14 (m, 1H), 0.79-0.71 (m, 1H).

Example 29: (rac)-(2s,4s)-2-(1-(3-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 3-bromodiphenyl ether instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₄H₂₄N₂O₄, 404.2; m/z found, 405.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.38-7.31 (m, 2H), 7.30-7.24 (m, 1H), 7.15-7.08 (m, 1H), 6.99 (d, J=8.5 Hz, 2H), 6.91 (dd, J=11.4, 7.9 Hz, 1H), 6.87-6.81 (m, 2H), 5.96 (d, J=17.2 Hz, 1H), 4.35 (d, J=1.0 Hz, 2H), 4.25-3.89 (m, 1H), 3.88-3.54 (m, 3H), 2.94-2.80 (m, 1H), 2.69-2.57 (m, 2H), 2.55-2.41 (m, 2H), 1.98-1.82 (m, 1H), 1.19-1.14 (m, 1H), 0.78 (dd, J=10.8, 5.1 Hz, 1H).

Example 30: (rac)-(2s,4s)-2-(1-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 4-bromo-2-chlorotoluene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₂₁ClN₂O₃, 360.1; m/z found, 361.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.20-7.12 (m, 2H), 7.04-6.92 (m, 1H), 5.85 (s, 1H), 4.35 (d, J=1.5 Hz, 2H), 4.25-3.89 (m, 1H), 3.82-3.54 (m, 3H), 2.95-2.80 (m, 1H), 2.68-2.56 (m, 2H), 2.55-2.44 (m, 2H), 2.34 (d, J=2.2 Hz, 3H), 1.95-1.85 (m, 1H), 1.17-1.13 (m, 1H), 0.81-0.70 (m, 1H).

Example 31: (rac)-(2s,4s)-2-(1-(3-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-(1-methylcyclopropyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₆N₂O₃, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.25-7.20 (m, 1H), 7.16-7.10 (m, 1H), 7.09-7.06 (m, 1H), 7.02-6.93 (m, 1H), 6.07 (d, J 27.9 Hz, 1H), 4.36 (d, J=3.0 Hz, 2H), 4.25-3.89 (m, 1H), 3.88-3.56 (m, 3H), 2.98-2.80 (m, 1H), 2.69-2.59 (m, 2H), 2.56-2.42 (m, 2H), 1.97-1.86 (m, 1H), 1.39 (d, J=2.8 Hz, 3H), 1.19-1.13 (m, 1H), 0.87-0.82 (m, 2H), 0.80-0.71 (m, 3H).

Example 32: (rac)-(2s,4s)-2-(1-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-cyclopropyl-2-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₆N₂O₃, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.20-7.09 (m, 1H), 6.94-6.78 (m, 2H), 6.17 (d, J=40.5 Hz, 1H), 4.42-4.29 (m, 2H), 4.13-3.92 (m, 1H), 3.87-3.58 (m, 2H), 3.47-3.28 (m, 1H), 2.92-2.75 (m, 1H), 2.69-2.57 (m, 2H), 2.55-2.36 (m, 2H), 2.34 (d, J=2.8 Hz, 3H), 1.90-1.73 (m, 2H), 1.08 (ddd, J=17.8, 7.8, 5.1 Hz, 1H), 0.99-0.88 (m, 2H), 0.74-0.59 (m, 3H).

Example 33: (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-2-methyl-4-(trifluoromethyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.1; m/z found, 395.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.46-7.32 (m, 3H), 6.06 (d, J=22.0 Hz, 1H), 4.39-4.26 (m, 2H), 4.18-3.97 (m, 1H), 3.86-3.61 (m, 2H), 3.49-3.30 (m, 1H), 2.94-2.76 (m, 1H), 2.69-2.57 (m, 2H), 2.55-2.38 (m, 5H), 1.91-1.82 (m, 1H), 1.19-1.07 (m, 1H), 0.85-0.79 (m, 1H).

Example 34: (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-2-methyl-4-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.27 (dd, J=11.6, 8.3 Hz, 1H), 7.04-6.95 (m, 2H), 5.96 (d, J=15.4 Hz, 1H), 4.34 (d, J=16.7 Hz, 2H), 4.16-3.95 (m, 1H), 3.86-3.60 (m, 2H), 3.48-3.29 (m, 1H), 2.97-2.75 (m, 1H), 2.69-2.41 (m, 4H), 2.40 (d, J=1.9 Hz, 3H), 1.87-1.78 (m, 1H), 1.17-1.05 (m, 1H), 0.81-0.75 (m, 1H).

Example 35: (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-methyl-4-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.18-7.09 (m, 1H), 7.06 (s, 1H), 7.01 (td, J=8.6, 1.9 Hz, 1H), 6.25 (d, J=5.1 Hz, 1H), 4.36 (d, J=4.4 Hz, 2H), 4.25-3.89 (m, 1H), 3.85-3.57 (m, 3H), 2.96-2.81 (m, 1H), 2.71-2.60 (m, 2H), 2.55-2.41 (m, 2H), 2.30 (d, J=2.6 Hz, 3H), 1.97-1.86 (m, 1H), 1.17-1.11 (m, 1H), 0.81-0.74 (m, 1H).

Example 36: (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-methyl-4-(trifluoromethyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.1; m/z found, 395.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.54 (dd, J=8.5, 3.0 Hz, 1H), 7.08-7.01 (m, 2H), 5.98 (s, 1H), 4.36 (d, J=1.7 Hz, 2H), 4.25-3.95 (m, 1H), 3.91-3.56 (m, 3H), 2.95-2.84 (m, 1H), 2.68-2.57 (m, 2H), 2.57-2.48 (m, 2H), 2.47 (s, 3H), 2.04-1.92 (m, 1H), 1.18 (t, J=6.7 Hz, 1H), 0.87-0.79 (m, 1H).

Example 37: (rac)-(2s,4s)-2-(1-(3-Fluoro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-3-fluoro-4-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₂₁FN₂O₃, 344.2; m/z found, 345.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.11 (td, J=8.0, 2.5 Hz, 1H), 6.89-6.77 (m, 2H), 6.09 (d, J=9.1 Hz, 1H), 4.36 (d, J=1.9 Hz, 2H), 4.25-3.89 (m, 1H), 3.84-3.53 (m, 3H), 2.95-2.80 (m, 1H), 2.69-2.57 (m, 2H), 2.55-2.41 (m, 2H), 2.26-2.22 (m, 3H), 1.94-1.84 (m, 1H), 1.17-1.08 (m, 1H), 0.82-0.70 (m, 1H).

Example 38: (2s,4S)-2-((1R,5S,6S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: 2-(Diiodomethyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. In an oven-dried pressure vial under N₂, pinacol(dichloromethyl)boronate (0.4 mL, 2.08 mmol) was taken up in acetone (4.4 mL). To this was added NaI (721 mg, 4.78 mmol) and the reaction was heated to 55° C. for 72 h. The reaction was cooled to rt, filtered through Celite® with acetone, and concentrated under reduced pressure. The residue was taken up in DCM and excess iodine was quenched with sodium thiosulfate and magnesium sulfate by shaking the flask until the orange color disappeared. The slurry was filtered through Celite® with DCM, concentrated under reduced pressure, and used without further purification in subsequent steps. Compound does not ionize with ESI⁺ LCMS.

Step B: tert-butyl (1R,5S,6s)-6-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate. In an oven-dried flask under N₂, chromium(II) chloride (1.0 g, 8.14 mmol) was taken up in THF (13.5 mL). TMEDA (1.22 mL, 8.14 mmol) was added and this was stirred at rt for 25 min. 2-(Diiodomethyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (801 mg, 2.03 mmol) was added and this was stirred at rt for 30 min. Finally, tert-butyl 2,5 dihydro-1H-pyrrole-1-carboxylate (237 mg, 1.36 mmol) was added and this was stirred at 50° C. for 20 h. The reaction was quenched with water and extracted with EtOAc. The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and concentrated under reduced pressure. The crude material was purified by FCC on silica (0-15-50% EtOAc in hexane) to afford the title compound (62 mg, 15% yield). MS (ESI): mass calcd. for C₁₆H₂₈BNO₄, 309.2; m/z found, 254.2 [M+2H−tBu]⁺.

Step C: tert-Butyl (1R,5S,6s)-6-(3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carboxylate. In an oven-dried pressure vial under N₂ was combined bis(dibenzylideneacetone)palladium (Pd(dba)₂) (1.9 mg, 0.003 mmol), 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (SPhos) (2.7 mg, 0.006 mmol), potassium tert-butoxide (KOtBu) (29 mg, 0.259 mmol), 1-iodo-3-(trifluoromethoxy)benzene (31 μL, 0.194 mmol), tert-butanol (0.26 mL), and 1,2-dimethoxyethane (DME) (0.78 mL). To this was added tert-butyl (1R,5S,6s)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate (20 mg, 0.065 mmol) and this was heated to 80° C. for 20 h. The reaction was quenched with water and extracted with EtOAc. The combined organic layers were dried over sodium sulfate, filtered, and concentrated under reduced pressure. Purification via reverse phase HPLC (5-95% ACN in 20 mM NH₄OH in water) afforded the title compound (6 mg, 27% yield). MS (ESI): mass calcd. for C₁₇H₂₀F₃NO₃, 343.1; m/z found, 288.1 [M+2H−tBu]⁺.

Step D: (1R,5S,6s)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane hydrochloride. To tert-butyl (1R,5S,6s)-6-(3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carboxylate (6 mg, 0.017 mmol) in MeOH (0.1 mL) was added HCl in 1,4-dioxane (4 M, 0.1 mL). This was heated to 45° C. for 1 hour before concentrating under reduced pressure. The title compound was used without further purification in the next step. MS (ESI): mass calcd. for C₁₂H₁₃ClF₃NO 279.1; m/z found, 244.1 [M−Cl]⁺.

Step E: (2s,4S)-2-((1R,5S,6S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. (1R,5S,6s)-6-(3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane hydrochloride was taken up in DMF (0.2 mL) and to this was added (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 3.1 mg, 0.018 mmol), DIPEA (9.2 μL, 0.052 mmol), and HATU (7.5 mg, 0.019 mmol). The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was filtered through a PTFE filter with MeOH and purified via reverse phase HPLC (5-95% ACN in 20 mM NH₄OH in water) to afford the title compound (6 mg, 87% yield). MS (ESI): mass calcd. for C₁₉H₁₉F₃N₂O₄, 396.1; m/z found, 397.3 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.29 (d, J=8.0 Hz, 1H), 7.06-7.01 (m, 1H), 6.95 (dt, J=7.7, 1.3 Hz, 1H), 6.85 (dt, J=2.5, 1.2 Hz, 1H), 6.22 (s, 1H), 4.36 (s, 2H), 4.00 (d, J=12.3 Hz, 1H), 3.72-3.63 (m, 2H), 3.57 (dd, J=12.3, 3.4 Hz, 1H), 2.88 (tt, J=8.5, 7.0 Hz, 1H), 2.71-2.59 (m, 2H), 2.54-2.44 (m, 2H), 1.97-1.86 (m, 2H), 1.67 (d, J=3.5 Hz, 1H).

Example 39: (rac)-(2s,4s)-2-(6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 1 using 6-phenyl-3-azabicyclo[4.1.0]heptane hydrochloride instead of 1-(p-tolyl)-3-azabicyclo[3.1.0]hexane. MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.1 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.34-7.16 (m, 5H), 6.28 (d, J=12.9 Hz, 1H), 4.38 (d, J=8.8 Hz, 2H), 4.03-3.63 (m, 2H), 3.56-3.42 (m, 1H), 3.41-3.18 (m, 1H), 2.98 (dp, J=18.7, 8.1 Hz, 1H), 2.75-2.62 (m, 2H), 2.55-2.40 (m, 2H), 2.24-2.03 (m, 2H), 1.56-1.37 (m, 1H), 1.09-1.01 (m, 1H), 0.79 (q, J=5.0 Hz, 1H).

Example 40: (2s,4S)-2-((1R,6S)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 39 (Stationary phase: Chiralpak AD, 5 μm 250×21 mm, Mobile phase: 40% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 60% CO₂). MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.34-7.16 (m, 5H), 6.42 (d, J=14.0 Hz, 1H), 4.38 (d, J=10.8 Hz, 2H), 4.03-3.58 (m, 2H), 3.50 (dp, J=19.0, 6.9 Hz, 1H), 3.41-3.18 (m, 1H), 2.98 (dp, J=24.2, 8.2 Hz, 1H), 2.70 (qd, J=10.4, 5.3 Hz, 2H), 2.47 (td, J=12.5, 8.2 Hz, 2H), 2.22-2.02 (m, 2H), 1.56-1.37 (m, 1H), 1.05 (dt, J=9.1, 4.8 Hz, 1H), 0.79 (q, J=5.4 Hz, 1H).

Example 41: (2s,4R)-2-((1S,6R)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 39 (Stationary phase: Chiralpak AD, 5 μm 250×21 mm, Mobile phase: 40% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 60% CO₂). MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.29 (t, J=7.6 Hz, 2H), 7.25-7.16 (m, 3H), 6.55 (d, J=11.8 Hz, 1H), 4.38 (d, J=10.7 Hz, 2H), 4.03-3.60 (m, 2H), 3.50 (dp, J=19.0, 6.9 Hz, 1H), 3.41-3.18 (m, 1H), 2.97 (dp, J=24.4, 8.2 Hz, 1H), 2.70 (qd, J=10.4, 5.3 Hz, 2H), 2.47 (td, J=12.5, 8.2 Hz, 2H), 2.22-2.02 (m, 2H), 1.53-1.38 (m, 1H), 1.09-1.01 (m, 1H), 0.78 (q, J=5.4 Hz, 1H).

Example 42: (rac)-(2s,4s)-2-(7,7-Difluoro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 1 using 7,7-difluoro-6-phenyl-3-azabicyclo[4.1.0]heptane hydrochloride instead of 1-(p-tolyl)-3-azabicyclo[3.1.0]hexane. MS (ESI): mass calcd. for C₁₉H₂₀F₂N₂O₃, 362.1; m/z found, 363.2 [M+H]⁺. ¹H NMR (500 MHz, CD₃OD) δ 7.42-7.24 (m, 5H), 4.51 (d, J=0.7 Hz, 1H), 4.48-4.42 (m, 1H), 4.05-3.76 (m, 2H), 3.73-3.50 (m, 1H), 3.30-3.01 (m, 2H), 2.64-2.37 (m, 4H), 2.34-2.12 (m, 2H), 2.01-1.85 (m, 1H).

Example 43: (rac)-(2s,4s)-2-(6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 3-bromotoluene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.19 (t, J=7.6 Hz, 1H), 7.07-6.99 (m, 3H), 5.75 (d, J=20.8 Hz, 1H), 4.37 (d, J=8.8 Hz, 2H), 4.02-3.86 (m, 1H), 3.74 (ddd, J=15.3, 13.1, 3.3 Hz, 1H), 3.56-3.41 (m, 1H), 3.39-3.17 (m, 1H), 3.07-2.92 (m, 1H), 2.71-2.59 (m, 2H), 2.54-2.44 (m, 2H), 2.33 (s, 3H), 2.22-2.01 (m, 2H), 1.52-1.37 (m, 1H), 1.08-1.02 (m, 1H), 0.79-0.72 (m, 1H).

Example 44: (2s,4*R)-2-((1*S,6*R)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 43 (Stationary phase: Chiralpak AD, 5 μm 250×21 mm, Mobile phase: 40% MeOH with 0.2% TEA, 60% CO₂). MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.1 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.18 (t, J=7.5 Hz, 1H), 7.07-6.98 (m, 3H), 6.20 (d, J=13.5 Hz, 1H), 4.38 (d, J=8.6 Hz, 2H), 4.02-3.40 (m, 3H), 3.40-3.17 (m, 1H), 3.12-2.89 (m, 1H), 2.74-2.61 (m, 2H), 2.54-2.41 (m, 2H), 2.33 (s, 3H), 2.21-2.06 (m, 2H), 1.52-1.36 (m, 1H), 1.04 (dt, J=9.0, 4.7 Hz, 1H), 0.76 (td, J=5.3, 2.9 Hz, 1H).

Example 45: (2s,4*S)-2-((1*R,6*S)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 43 (Stationary phase: Chiralpak AD, 5 μm 250×21 mm, Mobile phase: 40% MeOH with 0.2% TEA, 60% CO₂). MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.18 (dd, J=8.0, 7.1 Hz, 1H), 7.06-6.97 (m, 3H), 6.25-6.11 (m, 1H), 4.38 (d, J=8.6 Hz, 2H), 4.02-3.39 (m, 3H), 3.39-3.18 (m, 1H), 3.05-2.89 (m, 1H), 2.72-2.61 (m, 2H), 2.53-2.41 (m, 2H), 2.33 (s, 3H), 2.22-2.05 (m, 2H), 1.52-1.34 (m, 1H), 1.04 (dt, J=9.1, 4.7 Hz, 1H), 0.76 (td, J=5.3, 2.9 Hz, 1H).

Example 46: (rac)-(2s,4s)-2-(6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-fluoro-4-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₃FN₂O₃, 358.2; m/z found, 359.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.09 (t, J=8.0 Hz, 1H), 6.92-6.77 (m, 2H), 6.00 (d, J=18.1 Hz, 1H), 4.37 (d, J=7.9 Hz, 2H), 3.99-3.86 (m, 1H), 3.73 (ddd, J=15.3, 13.2, 3.3 Hz, 1H), 3.56-3.41 (m, 1H), 3.39-3.18 (m, 1H), 3.06-2.90 (m, 1H), 2.72-2.59 (m, 2H), 2.53-2.41 (m, 2H), 2.23 (d, J=1.6 Hz, 3H), 2.18-2.01 (m, 2H), 1.51-1.33 (m, 1H), 1.06-0.97 (m, 1H), 0.81-0.71 (m, 1H).

Example 47: (2s,4*R)-2-((1*S,6*R)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 46 (Stationary phase: Chiralcel OD-H 5 μm 250×20 mm, Mobile phase: 15% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 85% CO₂). MS (ESI): mass calcd. for C₂₀H₂₃FN₂O₃, 358.2; m/z found, 359.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.08 (td, J=8.0, 0.9 Hz, 1H), 6.91-6.82 (m, 2H), 6.37 (d, J=13.7 Hz, 1H), 4.37 (d, J=7.8 Hz, 2H), 3.98-3.61 (m, 2H), 3.55-3.39 (m, 1H), 3.39-3.17 (m, 1H), 3.03-2.89 (m, 1H), 2.73-2.61 (m, 2H), 2.53-2.41 (m, 2H), 2.22 (d, J=1.8 Hz, 3H), 2.19-2.00 (m, 2H), 1.51-1.33 (m, 1H), 1.02 (dt, J=9.1, 5.2 Hz, 1H), 0.78 (q, J=5.2 Hz, 1H).

Example 48: (2s,4*S)-2-((1*R,6*S)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 46 (Stationary phase: Chiralcel OD-H 5 μm 250×20 mm, Mobile phase: 15% MeOH:isopropanol (1:1) with 0.2% isopropylamine, 85% CO₂). MS (ESI): mass calcd. for C₂₀H₂₃FN₂O₃, 358.2; m/z found, 359.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.09 (td, J=8.1, 0.9 Hz, 1H), 6.91-6.82 (m, 2H), 6.27 (d, J=14.9 Hz, 1H), 4.37 (d, J=7.8 Hz, 2H), 3.98-3.61 (m, 2H), 3.56-3.40 (m, 1H), 3.39-3.17 (m, 1H), 3.05-2.89 (m, 1H), 2.72-2.62 (m, 2H), 2.52-2.41 (m, 2H), 2.23 (d, J=1.8 Hz, 3H), 2.20-2.00 (m, 2H), 1.51-1.33 (m, 1H), 1.02 (dt, J=9.0, 5.4 Hz, 1H), 0.78 (q, J=5.2 Hz, 1H).

Example 49: (rac)-(2s,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.31 (t, J=8.2 Hz, 1H), 7.15 (dd, J=6.5, 1.3 Hz, 1H), 7.05 (d, J=7.6 Hz, 2H), 6.25 (d, J=14.0 Hz, 1H), 4.38 (d, J=8.0 Hz, 2H), 3.98-3.92 (m, 1H), 3.76 (ddd, J=15.3, 13.2, 3.3 Hz, 1H), 3.58-3.43 (m, 1H), 3.41-3.21 (m, 1H), 3.07-2.90 (m, 1H), 2.74-2.63 (m, 2H), 2.55-2.43 (m, 2H), 2.24-2.05 (m, 2H), 1.57-1.38 (m, 1H), 1.11-1.02 (m, 1H), 0.87-0.80 (m, 1H).

Example 50: (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 49 (Stationary phase: Chiralpak AD, 5 μm 250×30 mm, Mobile phase: 25% MeOH with 0.2% TEA, 75% CO₂). MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.1 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.35-7.28 (m, 1H), 7.17-7.13 (m, 1H), 7.08-7.03 (m, 2H), 5.90 (d, J=23.3 Hz, 1H), 4.38 (d, J=10.1 Hz, 2H), 4.00-3.90 (m, 1H), 3.85-3.65 (m, 1H), 3.56-3.44 (m, 1H), 3.39-3.22 (m, 1H), 3.05-2.91 (m, 1H), 2.70-2.59 (m, 2H), 2.54-2.44 (m, 2H), 2.21-2.05 (m, 2H), 1.55-1.40 (m, 1H), 1.07 (td, J=8.7, 5.4 Hz, 1H), 0.84 (q, J=5.5 Hz, 1H).

Example 51: (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 49 (Stationary phase: Chiralpak AD, 5 μm 250×30 mm, Mobile phase: 25% MeOH with 0.2% TEA, 75% CO₂). MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.1 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.34-7.28 (m, 1H), 7.18-7.12 (m, 1H), 7.08-7.03 (m, 2H), 6.09 (d, J=19.8 Hz, 1H), 4.38 (d, J=10.0 Hz, 2H), 3.99-3.90 (m, 1H), 3.86-3.64 (m, 1H), 3.56-3.44 (m, 1H), 3.39-3.21 (m, 1H), 3.05-2.91 (m, 1H), 2.72-2.60 (m, 2H), 2.54-2.44 (m, 2H), 2.21-2.04 (m, 2H), 1.55-1.40 (m, 1H), 1.07 (td, J=8.7, 5.4 Hz, 1H), 0.84 (q, J=5.6 Hz, 1H).

Example 52: (rac)-(2r,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₃, 408.2; m/z found, 409.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.43 (t, J=7.9 Hz, 1H), 7.29 (d, J=7.3 Hz, 1H), 7.21-7.14 (m, 2H), 3.91-3.56 (m, 2H), 3.43-3.35 (m, 1H), 3.29-3.22 (m, 1H), 3.09-2.98 (m, 1H), 2.36-2.17 (m, 4H), 2.17-2.11 (m, 4H), 2.11-1.99 (m, 2H), 1.54-1.44 (m, 1H), 1.05-0.97 (m, 1H), 0.84 (t, J=5.3 Hz, 1H).

Example 53: (rac)-(2s,4s)-2-(6-(o-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 2-bromotoluene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.21-7.10 (m, 4H), 5.78 (d, J=23.5 Hz, 1H), 4.38 (d, J=13.0 Hz, 2H), 4.05-3.92 (m, 1H), 3.90-3.63 (m, 2H), 3.34-3.22 (m, 1H), 3.10-2.91 (m, 1H), 2.71-2.61 (m, 2H), 2.56-2.44 (m, 2H), 2.38 (s, 3H), 2.11-1.87 (m, 2H), 1.48-1.34 (m, 1H), 1.04-0.94 (m, 1H), 0.74 (dd, J=9.1, 5.1 Hz, 1H).

Example 54: (rac)-(2s,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.26-7.22 (m, 2H), 7.14 (d, J=8.2 Hz, 2H), 6.00 (d, J=15.6 Hz, 1H), 4.38 (d, J=8.5 Hz, 2H), 4.03-3.65 (m, 2H), 3.59-3.41 (m, 1H), 3.40-3.18 (m, 1H), 3.08-2.92 (m, 1H), 2.73-2.61 (m, 2H), 2.57-2.43 (m, 2H), 2.20-2.02 (m, 2H), 1.55-1.38 (m, 1H), 1.09-1.00 (m, 1H), 0.86-0.77 (m, 1H).

Example 55: (rac)-(2r,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-(trifluoromethoxy)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₃, 408.2; m/z found, 409.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.37 (d, J=8.6 Hz, 2H), 7.27 (d, J=8.2 Hz, 2H), 3.90-3.54 (m, 2H), 3.43-3.35 (m, 1H), 3.28-3.23 (m, 1H), 3.10-2.95 (m, 1H), 2.40-2.24 (m, 3H), 2.24-2.17 (m, 2H), 2.13 (s, 4H), 1.50-1.37 (m, 1H), 1.06-0.94 (m, 1H), 0.94-0.73 (m, Hz, 2H).

Example 56: (rac)-(2s,4s)-2-(6-(p-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 4-bromotoluene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.16-7.08 (m, 4H), 5.88 (d, J=19.8 Hz, 1H), 4.37 (d, J=8.9 Hz, 2H), 4.03-3.62 (m, 2H), 3.48 (td, J=6.7, 2.5 Hz, 1H), 3.40-3.18 (m, 1H), 3.09-2.92 (m, 1H), 2.71-2.60 (m, 2H), 2.55-2.42 (m, 2H), 2.32 (s, 3H), 2.21-2.00 (m, 2H), 1.51-1.34 (m, 1H), 1.06-0.99 (m, 1H), 0.79-0.72 (m, 1H).

Example 57: (rac)-(2s,4s)-2-(6-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-(trifluoromethyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.1; m/z found, 395.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.47 (dd, J=5.6, 3.1 Hz, 2H), 7.42 (dd, J=6.1, 1.5 Hz, 2H), 5.88 (d, J=18.2 Hz, 1H), 4.38 (d, J=8.7 Hz, 2H), 3.96 (d, J=3.5 Hz, 1H), 3.77 (ddd, J=15.2, 13.2, 3.2 Hz, 1H), 3.60-3.43 (m, 1H), 3.41-3.21 (m, 1H), 3.11-2.91 (m, 1H), 2.75-2.59 (m, 2H), 2.57-2.45 (m, 2H), 2.18-2.10 (m, 2H), 1.59-1.41 (m, 1H), 1.14-1.03 (m, 1H), 0.92-0.77 (m, 1H).

Example 58: (rac)-(2s,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-(trifluoromethyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.1; m/z found, 395.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.55 (d, J=8.2 Hz, 2H), 7.33 (d, J=7.5 Hz, 2H), 6.35 (d, J=11.1 Hz, 1H), 4.38 (d, J=8.0 Hz, 2H), 3.99-3.90 (m, 1H), 3.89-3.65 (m, 1H), 3.60-3.43 (m, 1H), 3.43-3.21 (m, 1H), 3.07-2.88 (m, 1H), 2.74-2.63 (m, 2H), 2.54-2.42 (m, 2H), 2.24-2.06 (m, 2H), 1.59-1.41 (m, 1H), 1.12-1.03 (m, 1H), 0.86 (dd, J=9.3, 5.3 Hz, 1H).

Example 59: (rac)-(2r,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-(trifluoromethyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₂, 392.2; m/z found, 393.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.64 (d, J=8.3 Hz, 2H), 7.46 (d, J=8.2 Hz, 2H), 3.90-3.59 (m, 2H), 3.44-3.35 (m, 1H), 3.29-3.25 (m, 1H), 3.11-2.97 (m, 1H), 2.35-2.26 (m, 2H), 2.24-2.01 (m, 8H), 1.57-1.45 (m, 1H), 1.10-0.99 (m, 1H), 0.88 (t, J=5.4 Hz, 1H).

Example 60: (rac)-(2s,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-(tert-butyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₃H₃₀N₂O₃, 382.2; m/z found, 383.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.25-7.22 (m, 3H), 7.08-7.01 (m, 1H), 6.04 (d, J=16.3 Hz, 1H), 4.38 (d, J=9.0 Hz, 2H), 4.03-3.63 (m, 2H), 3.50 (t, J=6.4 Hz, 1H), 3.41-3.19 (m, 1H), 3.08-2.92 (m, 1H), 2.73-2.61 (m, 2H), 2.55-2.41 (m, 2H), 2.26-2.05 (m, 2H), 1.55-1.38 (m, 1H), 1.31 (s, 9H), 1.09-0.99 (m, 1H), 0.82-0.73 (m, 1H).

Example 61: (rac)-(2r,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-(tert-butyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₄H₃₂N₂O₂, 380.2; m/z found, 381.2 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.25-7.16 (m, 3H), 7.08-7.01 (m, 1H), 3.92-3.55 (m, 2H), 3.32-3.17 (m, 2H), 3.10-2.95 (m, 1H), 2.36-2.16 (m, 4H), 2.15-2.12 (m, 4H), 2.08-1.94 (m, 2H), 1.47-1.36 (m, 1H), 1.26 (s, J=11.3 Hz, 9H), 0.98-0.90 (m, 1H), 0.78 (q, J=5.1 Hz, 1H).

Example 62: (rac)-(2s,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) in Step A. MS (ESI): mass calcd. for C₂₃H₃₀N₂O₃, 382.2; m/z found, 383.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.34-7.29 (m, 2H), 7.15 (dd, J=8.3, 1.2 Hz, 2H), 6.03 (d, J=16.0 Hz, 1H), 4.37 (d, J=8.2 Hz, 2H), 4.03-3.61 (m, 2H), 3.48 (t, J=6.4 Hz, 1H), 3.39-3.17 (m, 1H), 3.06-2.88 (m, 1H), 2.71-2.60 (m, 2H), 2.53-2.40 (m, 2H), 2.25-2.06 (m, 2H), 1.53-1.36 (m, 1H), 1.30 (s, 9H), 1.08-1.02 (m, 1H), 0.77 (dd, J=11.4, 5.5 Hz, 1H).

Example 63: (rac)-(2r,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₄H₃₂N₂O₂, 380.2; m/z found, 381.2 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.29 (d, J=8.3 Hz, 2H), 7.15 (d, J=8.3 Hz, 2H), 3.90-3.55 (m, 2H), 3.42-3.37 (m, 1H), 3.29-3.17 (m, 1H), 3.11-2.94 (m, 1H), 2.37-2.18 (m, 4H), 2.13 (d, J=6.1 Hz, 4H), 2.08-1.92 (m, 2H), 1.44-1.31 (m, 1H), 1.25 (s, 9H), 0.98-0.88 (m, 1H), 0.76 (t, J=4.8 Hz, 1H).

Example 64: (rac)-(2s,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-cyclopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₆N₂O₃, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.18 (t, J=7.6 Hz, 1H), 7.04-6.98 (m, 1H), 6.97 (br s, 1H), 6.87 (d, J=7.6 Hz, 1H), 5.94 (d, J=18.3 Hz, 1H), 4.37 (d, J=8.8 Hz, 2H), 4.03-3.61 (m, 2H), 3.59-3.41 (m, 1H), 3.39-3.17 (m, 1H), 3.09-2.89 (m, 1H), 2.73-2.56 (m, 2H), 2.55-2.40 (m, 2H), 2.23-2.01 (m, 2H), 1.93-1.79 (m, 1H), 1.53-1.37 (m, 1H), 1.08-1.00 (m, 1H), 1.00-0.90 (m, 2H), 0.79-0.71 (m, 1H), 0.70-0.60 (m, 2H).

Example 65: (rac)-(2r,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-cyclopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₃H₂₈N₂O₂, 364.2; m/z found, 365.2 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.15 (t, J=7.6 Hz, 1H), 7.03-6.93 (m, 2H), 6.83 (d, J=7.7 Hz, 1H), 3.89-3.56 (m, 2H), 3.41-3.36 (m, 1H), 3.30-3.19 (m, 1H), 3.10-2.95 (m, 1H), 2.35-2.16 (m, 4H), 2.16-2.11 (m, 4H), 2.06-1.95 (m, 2H), 1.88 (tt, J=8.4, 5.1 Hz, 1H), 1.43-1.36 (m, 1H), 0.98-0.87 (m, 3H), 0.75 (t, J=5.2 Hz, 1H), 0.66-0.61 (m, 2H).

Example 66: (rac)-(2s,4s)-2-(6-(4-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-cyclopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₆N₂O₃, 366.2; m/z found, 367.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.14-7.08 (m, 2H), 7.03-6.98 (m, 2H), 5.89 (d, J=19.0 Hz, 1H), 4.37 (d, J=8.8 Hz, 2H), 4.01-3.61 (m, 2H), 3.53-3.40 (m, 1H), 3.38-3.17 (m, 1H), 3.07-2.88 (m, 1H), 2.71-2.59 (m, 2H), 2.52-2.42 (m, 2H), 2.21-2.00 (m, 2H), 1.91-1.82 (m, 1H), 1.50-1.34 (m, 1H), 1.05-0.98 (m, 1H), 0.97-0.91 (m, 2H), 0.75 (q, J=5.2 Hz, 1H), 0.68-0.63 (m, 2H).

Example 67: (rac)-(2s,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-chloro-4-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₃ClN₂O₃, 374.1; m/z found, 375.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.20 (dd, J=6.3, 1.8 Hz, 1H), 7.14 (d, J=7.9 Hz, 1H), 7.01 (dt, J=7.8, 2.2 Hz, 1H), 5.83 (d, J=20.5 Hz, 1H), 4.37 (d, J=8.3 Hz, 2H), 4.01-3.87 (m, 1H), 3.73 (ddd, J=15.3, 13.2, 3.3 Hz, 1H), 3.58-3.40 (m, 1H), 3.37-3.17 (m, 1H), 3.08-2.91 (m, 1H), 2.70-2.60 (m, 2H), 2.54-2.44 (m, 2H), 2.33 (s, 3H), 2.21-1.99 (m, 2H), 1.50-1.34 (m, 1H), 1.06-0.99 (m, 1H), 0.81-0.73 (m, 1H).

Example 68: (rac)-(2r,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-chloro-4-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₁H₂₅ClN₂O₂, 372.2; m/z found, 373.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.25 (dd, J=4.6, 2.8 Hz, 2H), 7.11 (dt, J=7.9, 1.5 Hz, 1H), 3.90-3.54 (m, 2H), 3.31-3.18 (m, 2H), 3.10-2.95 (m, 1H), 2.33-2.24 (m, 5H), 2.23-2.16 (m, 2H), 2.16-2.10 (m, 4H), 2.06-1.94 (m, 2H), 1.49-1.36 (m, 1H), 1.01-0.90 (m, 1H), 0.76 (t, J=5.3 Hz, 1H).

Example 69: (rac)-(2s,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-(1-methylcyclopropyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₃H₂₈N₂O₃, 380.2; m/z found, 381.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.21-7.10 (m, 4H), 5.84 (d, J=19.3 Hz, 1H), 4.37 (d, J=8.6 Hz, 2H), 4.02-3.60 (m, 2H), 3.47 (t, J=6.4 Hz, 1H), 3.39-3.16 (m, 1H), 3.09-2.90 (m, 1H), 2.74-2.59 (m, 2H), 2.57-2.42 (m, 2H), 2.23-1.97 (m, 2H), 1.50-1.43 (m, 1H), 1.38 (s, 3H), 1.07-1.00 (m, 1H), 0.86-0.80 (m, 2H), 0.79-0.74 (m, 1H), 0.71 (dd, J=6.1, 4.2 Hz, 2H).

Example 70: (rac)-(2r,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-(1-methylcyclopropyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₄H₃₀N₂O₂, 378.2; m/z found, 379.2 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.91 (s, 1H), 7.11 (s, 4H), 3.89-3.60 (m, 2H), 3.26-3.16 (m, 2H), 3.07-2.92 (m, 1H), 2.32-2.23 (m, 2H), 2.23-2.08 (m, 6H), 2.04-1.88 (m, 2H), 1.39-1.27 (m, 4H), 0.95-0.87 (m, 1H), 0.80-0.64 (m, 5H).

Example 71: (rac)-(2s,4s)-2-(6-(3-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-(1-methylcyclopropyl)benzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₃H₂₈N₂O₃, 380.2; m/z found, 381.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.21 (t, J=7.6 Hz, 1H), 7.14-7.07 (m, 2H), 7.06-6.99 (m, 1H), 5.85 (d, J=19.7 Hz, 1H), 4.38 (d, J=8.8 Hz, 2H), 4.02-3.64 (m, 2H), 3.51-3.46 (m, 1H), 3.40-3.19 (m, 1H), 3.07-2.93 (m, 1H), 2.72-2.60 (m, 2H), 2.56-2.43 (m, 2H), 2.24-2.04 (m, 2H), 1.52-1.41 (m, 1H), 1.39 (s, 3H), 1.10-0.99 (m, 1H), 0.86-0.82 (m, 2H), 0.78 (q, J=5.4 Hz, 1H), 0.72 (dd, J=6.1, 4.2 Hz, 2H).

Example 72: (rac)-(2s,4s)-2-(6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-cyclopropyl-2-methylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₃H₂₈N₂O₃, 380.2; m/z found, 381.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.06 (dd, J=7.8, 4.1 Hz, 1H), 6.86 (s, 1H), 6.82 (d, J=7.8 Hz, 1H), 5.78 (d, J=24.4 Hz, 1H), 4.37 (d, J=12.7 Hz, 2H), 4.00-3.94 (m, 1H), 3.89-3.59 (m, 2H), 3.36-3.16 (m, 1H), 3.11-2.90 (m, 1H), 2.72-2.59 (m, 2H), 2.55-2.43 (m, 2H), 2.34 (s, 3H), 2.05-1.77 (m, 3H), 1.44-1.29 (m, 1H), 1.00-0.88 (m, 3H), 0.71 (dd, J=8.9, 5.1 Hz, 1H), 0.67-0.61 (m, 2H).

Example 73: (rac)-(2s,4s)-2-(6-(3-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-3-isopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₃, 368.2; m/z found, 369.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.25-7.20 (m, 1H), 7.10-7.02 (m, 3H), 5.77 (d, J=21.2 Hz, 1H), 4.37 (d, J=8.9 Hz, 2H), 4.03-3.63 (m, 2H), 3.53-3.46 (m, 1H), 3.42-3.17 (m, 1H), 3.10-2.94 (m, 1H), 2.92-2.83 (m, 1H), 2.71-2.60 (m, 2H), 2.57-2.44 (m, 2H), 2.24-2.02 (m, 2H), 1.54-1.38 (m, 1H), 1.24 (d, J=6.9 Hz, 6H), 1.09-1.03 (m, 1H), 0.78 (q, J=5.2 Hz, 1H).

Example 74: (rac)-(2s,4s)-2-(6-(4-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 1-bromo-4-isopropylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₃, 368.2; m/z found, 369.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.20-7.12 (m, 4H), 5.90 (d, J=18.9 Hz, 1H), 4.37 (d, J=8.5 Hz, 2H), 4.05-3.61 (m, 2H), 3.48 (t, J=6.4 Hz, 1H), 3.40-3.16 (m, 1H), 3.06-2.93 (m, 1H), 2.91-2.83 (m, 1H), 2.74-2.59 (m, 2H), 2.56-2.41 (m, 2H), 2.24-2.00 (m, 2H), 1.53-1.35 (m, 1H), 1.23 (d, J=6.9 Hz, 6H), 1.10-1.01 (m, 1H), 0.77 (q, J=5.3 Hz, 1H).

Example 75: (rac)-(2s,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 4-bromo-1-methyl-2-(trifluoromethoxy)benzene (Intermediate 8) instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₄, 424.2; m/z found, 425.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.17 (d, J=7.9 Hz, 1H), 7.07-7.01 (m, 2H), 5.93 (d, J=18.5 Hz, 1H), 4.37 (d, J=8.2 Hz, 2H), 4.02-3.63 (m, 2H), 3.55-3.43 (m, 1H), 3.40-3.19 (m, 1H), 3.08-2.90 (m, 1H), 2.72-2.60 (m, 2H), 2.56-2.42 (m, 2H), 2.27 (s, 3H), 2.20-2.03 (m, 2H), 1.52-1.36 (m, 1H), 1.07-0.97 (m, 1H), 0.85-0.75 (m, 1H).

Example 76: (rac)-(2r,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-6-yl)trifluoroborate (Intermediate 6) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using 4-bromo-1-methyl-2-(trifluoromethoxy)benzene (Intermediate 8) instead of 1-bromo-4-(tert-butyl)benzene in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step C. MS (ESI): mass calcd. for C₂₂H₂₅F₃N₂O₃, 422.2; m/z found, 423.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.30 (d, J=8.1 Hz, 1H), 7.18 (d, J=8.0 Hz, 1H), 7.11 (s, 1H), 3.89-3.56 (m, 2H), 3.42-3.37 (m, 1H), 3.28-3.20 (m, 1H), 3.09-2.94 (m, 1H), 2.35-2.25 (m, 2H), 2.24-2.16 (m, 5H), 2.16-2.10 (m, 4H), 2.07-1.97 (m, 2H), 1.49-1.38 (m, 1H), 1.01-0.92 (m, 1H), 0.84-0.76 (m, 1H).

Example 77: (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[4.1.0]heptan-1-yl)trifluoroborate (Intermediate 7) instead of potassium (3-(tert-butoxycarbonyl)-3-azabicyclo[3.1.0]hexan-1-yl)trifluoroborate (Intermediate 5) and using bromobenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.37-7.27 (m, 3H), 7.26-7.19 (m, 2H), 5.81 (d, J=16.9 Hz, 1H), 4.53-4.30 (m, 2H), 4.00-3.40 (m, 3H), 3.25-2.86 (m, 2H), 2.75-2.32 (m, 4H), 2.25-2.13 (m, 1H), 1.91-1.73 (m, 1H), 1.46-1.31 (m, 1H), 1.14-1.04 (m, 1H), 0.63 (dd, J=9.7, 5.1 Hz, 1H).

Example 78: (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: (3-(tert-Butyl)benzylidene)hydrazine. To hydrazine monohydrate (21.3 mL, 449 mmol) was added 3-tert-butylbenzaldehyde (7.1 g, 44 mmol) dropwise over 1 min at room temperature and the reaction mixture was stirred at room temperature for 20 min. The reaction mixture was poured into water and extracted with Et₂O. The combined organic layers were washed with water, dried over magnesium sulfate, filtered and evaporated under reduced pressure to give the title compound (7.3 g, 94% yield) as a yellow oil which was used without further purification in the next step. MS (ESI): mass calcd. for C₁₁H₁₆N₂, 176.1; m/z found, 177.2 [M+H]⁺.

Step B: (1R,5S,6s)-3-Benzyl-6-(3-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane-2,4-dione. To a solution of (3-(tert-butyl)benzylidene)hydrazine (7.3 g, 41 mmol) in 1,4-dioxane (70 mL) was added manganese(IV) oxide (15.1 g, 173 mmol) and the reaction mixture was stirred at room temperature for 2 h. The reaction mixture was filtered through a pad of Celite®. To the filtrate was added N-benzylmaleimide (7.7 g, 41 mmol) and the reaction mixture was stirred at 100° C. for 16 h. The reaction mixture was evaporated under reduced pressure and the residue was triturated with Et₂O to give the title compound (3.6 g, 26% yield) as a white powder. MS (ESI): mass calcd. for C₂₂H₂₃NO₂, 333.2; m/z found, 334.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 7.38-7.32 (m, 2H), 7.32-7.27 (m, 3H), 7.27-7.21 (m, 3H), 7.00-6.94 (m, 1H), 4.45 (s, 2H), 3.14-3.08 (m, 2H), 3.08-3.03 (m, 1H), 1.27 (s, 9H).

Step C: (1R,5S,6s)-3-Benzyl-6-(3-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane. To a suspension of (1R,5S,6s)-3-benzyl-6-(3-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane-2,4-dione (3.5 g, 11 mmol) in freshly distilled THF (10 mL) was added lithium aluminum hydride (LiAlH₄) (42 mL, 1 M in THF) dropwise at 0° C. over 10 min and the reaction mixture was stirred at 0° C. for 1 h under argon. The reaction mixture was allowed to warm to room temperature and stirred at room temperature for 16 h under argon. The reaction mixture was diluted with Et₂O and the reaction was quenched with sodium sulfate decahydrate. The mixture was filtered and the solid was washed with EtOAc. The combined filtrates were evaporated under reduced pressure and the residue was purified by FCC on silica (0-30% EtOAc in heptane) to give the title compound (1.7 g, 53% yield) as a white crystalline solid. MS (ESI): mass calcd. for C₂₂H₂₇N, 305.2; m/z found, 306.5 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 7.37-7.28 (m, 4H), 7.27-7.21 (m, 1H), 7.16-7.11 (m, 2H), 7.11-7.09 (m, 1H), 6.81-6.73 (m, 1H), 3.61 (s, 2H), 3.02 (d, J=8.9 Hz, 2H), 2.45-2.41 (m, 2H), 2.26-2.22 (m, 1H), 1.70-1.65 (m, 2H), 1.25 (s, 9H).

Step D: (1R,5S,6s)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane hydrochloride. To a solution of (1R,5S,6s)-3-benzyl-6-(3-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane (1.66 g, 5.43 mmol) in EtOH (15 mL) was added 10% Pd/C (580 mg, 0.54 mmol) and hydrogen chloride (HCl) (4.2 M in 1,4-dioxane, 3.9 mL). The reaction mixture was stirred at room temperature for 16 h under H₂ (1 bar). The reaction mixture was filtered through a pad of Celite®. To the filtrate was added 10% Pd/C (580 mg, 0.54 mmol) and the reaction mixture was stirred at room temperature for 72 h under H₂ (1 bar). The reaction mixture was filtered through a pad of Celite® and the Celite® was washed with EtOH. The combined filtrates were evaporated under reduced pressure and the product was triturated with Et₂O to give the title compound (940 mg, 69% yield) as a white powder. MS (ESI): mass calcd. for C₁₅H₂₁N, 215.2; m/z found, 216.3 [M+H]⁺.

Step E: (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. To a suspension of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 205 mg, 1.2 mmol) in DCM (5 mL) was added EDC (229 mg, 1.19 mmol), TEA (670 μL, 4.81 mmol) and HOBt (178 mg, 1.32 mmol). The reaction mixture was stirred at room temperature for 10 min. To the reaction mixture was added (1R,5S,6s)-6-(3-(tert-butyl)phenyl)-3-azabicyclo[3.1.0]hexane hydrochloride (300 mg, 1.19 mmol) and stirred at room temperature for 18 h. The reaction mixture was diluted with DCM and washed with 1 M potassium bisulfate, saturated NaHCO₃ and brine. The organic layer was dried over magnesium sulfate, filtered and evaporated under reduced pressure. The crude product was purified by preparative HPLC to give the title compound (235 mg, 54% yield) as a white powder. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₃, 368.2; m/z found, 369.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 8.07 (s, 1H), 7.20-7.14 (m, 2H), 7.13-7.10 (m, 1H), 6.83-6.77 (m, 1H), 4.37 (d, J=9.3 Hz, 1H), 4.35 (d, J=9.3 Hz, 1H), 3.74 (d, J=11.9 Hz, 1H), 3.68 (d, J=10.5 Hz, 1H), 3.55 (dd, J=10.5, 4.3 Hz, 1H), 3.36 (dd, J=11.9, 4.4 Hz, 1H), 2.94-2.83 (m, 1H), 2.44-2.27 (m, 4H), 1.95-1.90 (m, 1H), 1.88-1.82 (m, 1H), 1.64-1.59 (m, 1H), 1.25 (s, 9H).

Example 79: (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 78 using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step E. MS (ESI): mass calcd. for C₂₃H₃₀N₂O₂, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.23-7.17 (m, 2H), 7.08 (dd, J=2.0, 1.0 Hz, 1H), 6.81-6.75 (m, 1H), 6.56 (s, 1H), 3.97 (d, J=12.1 Hz, 1H), 3.72-3.58 (m, 2H), 3.54 (dd, J=12.2, 3.9 Hz, 1H), 2.89 (p, J=8.3 Hz, 1H), 2.61-2.50 (m, 2H), 2.43-2.31 (m, 4H), 2.25-2.17 (m, 2H), 1.88 (hept, J=3.7 Hz, 2H), 1.63 (t, J=3.5 Hz, 1H), 1.30 (s, 9H).

Example 80: (2s,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 78 using 4-trifluoromethylbenzaldehyde instead of 3-tert-butylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₁₉H₁₉F₃N₂O₃, 380.1; m/z found, 381.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 8.07 (s, 1H), 7.59 (d, J=8.1 Hz, 2H), 7.30 (d, J=8.1 Hz, 2H), 4.37 (d, J=8.7 Hz, 1H), 4.35 (d, J=8.8 Hz, 1H), 3.77 (d, J=12.0 Hz, 1H), 3.71 (d, J=10.6 Hz, 1H), 3.57 (dd, J=10.6, 4.3 Hz, 1H), 3.39 (dd, J=12.0, 4.4 Hz, 1H), 2.94-2.85 (m, 1H), 2.45-2.38 (m, 1H), 2.37-2.26 (m, 3H), 2.08-2.02 (m, 1H), 1.99-1.95 (m, 1H), 1.80-1.76 (m, 1H).

Example 81: (2r,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 78 using 4-trifluoromethylbenzaldehyde instead of 3-tert-butylbenzaldehyde in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step E. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₂, 378.2; m/z found, 379.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 7.95 (s, 1H), 7.59 (d, J=8.1 Hz, 2H), 7.30 (d, J=8.1 Hz, 2H), 3.77 (d, J=12.0 Hz, 1H), 3.73 (d, J=10.6 Hz, 1H), 3.58 (dd, J=10.6, 4.2 Hz, 1H), 3.38 (dd, J=12.0, 4.3 Hz, 1H), 2.96-2.86 (m, 1H), 2.37-2.30 (m, 1H), 2.29-2.23 (m, 1H), 2.22-2.17 (m, 2H), 2.16-2.09 (m, 4H), 2.06-2.01 (m, 1H), 1.99-1.93 (m, 1H), 1.81-1.75 (m, 1H).

Example 82: (2s,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 78 using 4-tert-butylbenzaldehyde instead of 3-tert-butylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₃, 368.2; m/z found, 369.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 8.06 (s, 1H), 7.30-7.21 (m, 2H), 7.03-6.94 (m, 2H), 4.37 (d, J=9.1 Hz, 1H), 4.35 (d, J=9.0 Hz, 1H), 3.73 (d, J=11.9 Hz, 1H), 3.67 (d, J=10.5 Hz, 1H), 3.54 (dd, J=10.5, 4.3 Hz, 1H), 3.36 (dd, J=11.9, 4.5 Hz, 1H), 2.94-2.84 (m, 1H), 2.44-2.37 (m, 1H), 2.37-2.27 (m, 3H), 1.93-1.86 (m, 1H), 1.85-1.78 (m, 1H), 1.59-1.54 (m, 1H), 1.24 (s, 9H).

Example 83: (2r,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 78 using 4-tert-butylbenzaldehyde instead of 3-tert-butylbenzaldehyde in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step E. MS (ESI): mass calcd. for C₂₃H₃₀N₂O₂, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 7.93 (s, 1H), 7.25-7.20 (m, 2H), 7.00-6.92 (m, 2H), 3.70 (d, J=11.9 Hz, 1H), 3.67 (d, J=10.5 Hz, 1H), 3.53 (dd, J=10.5, 4.3 Hz, 1H), 3.33 (dd, J=11.9, 4.4 Hz, 1H), 2.94-2.83 (m, 1H), 2.32-2.26 (m, 1H), 2.26-2.20 (m, 1H), 2.20-2.04 (m, 6H), 1.90-1.83 (m, 1H), 1.82-1.75 (m, 1H), 1.57-1.51 (m, 1H), 1.21 (s, 9H).

Example 84: (2s,4S)-2-((1R,5S,6S)-6-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 78 using 3-isopropylbenzaldehyde instead of 3-tert-butylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 8.05 (s, 1H), 7.13 (t, J=7.6 Hz, 1H), 7.00-6.96 (m, 1H), 6.95-6.91 (m, 1H), 6.83-6.77 (m, 1H), 4.35 (d, J=9.2 Hz, 1H), 4.32 (d, J=9.0 Hz, 1H), 3.71 (d, J=12.0 Hz, 1H), 3.65 (d, J=10.5 Hz, 1H), 3.52 (dd, J=10.5, 4.3 Hz, 1H), 3.34 (dd, J=11.9, 4.4 Hz, 1H), 2.91-2.75 (m, 2H), 2.41-2.23 (m, 4H), 1.92-1.87 (m, 1H), 1.85-1.79 (m, 1H), 1.58-1.54 (m, 1H), 1.15 (d, J=6.9 Hz, 6H).

Example 85: (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 78 using 4-methyl-3-trifluoromethylbenzaldehyde instead of 3-tert-butylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₀H₂₁N₂O₃, 394.2; m/z found, 395.2 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 8.07 (s, 1H), 7.40-7.36 (m, 1H), 7.31 (d, J=7.9 Hz, 1H), 7.25-7.20 (m, 1H), 4.38 (d, J=9.2 Hz, 1H), 4.34 (d, J=9.1 Hz, 1H), 3.75 (d, J=11.9 Hz, 1H), 3.68 (d, J=10.5 Hz, 1H), 3.55 (dd, J=10.6, 4.3 Hz, 1H), 3.36 (dd, J=12.0, 4.4 Hz, 1H), 2.93-2.82 (m, 1H), 2.39-2.36 (m, 3H), 2.43-2.27 (m, 4H), 2.02-1.97 (m, 1H), 1.94-1.89 (m, 1H), 1.77-1.72 (m, 1H).

Example 86: (2s,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: N′-(4-Ethylbenzylidene)-4-methylbenzenesulfonohydrazide. To a solution of 4-ethylbenzaldehyde (2.0 g, 15 mmol) in THF (40 mL) was added 4-methylbenzenesulfonhydrazide (2.8 g, 15 mmol) and the reaction stirred at room temperature for 3 h. Na₂SO₄ was added, the mixture was filtered, and the filtrate was concentrated under reduced pressure to afford the title compound as a white solid in quantitative yield. MS (ESI): mass calcd. for C₁₆H₁₈N₂O₂S, 302.1; m/z found, 302.9 [M+H]⁺.

Step B: (1R,5S,6s)-3-Benzyl-6-(4-ethylphenyl)-3-azabicyclo[3.1.0]hexane. To a solution of N′-(4-ethylbenzylidene)-4-methylbenzenesulfonohydrazide (500 mg, 1.65 mmol) in THF (30 mL) was added NaH (60% dispersion in mineral oil, 80 mg, 2.00 mmol). The reaction was then heated with stirring at 60° C. for 1 h whereupon the reaction turned into a red slurry. After cooling to room temperature, the mixture was filtered, and the filtrate carefully concentrated in vacuo using a room temperature water bath to yield crude diazo intermediate. The crude residue was then dissolved in DCM (15 mL) and the solution added dropwise over 15 minutes to a stirring mixture of 1-benzyl-2,5-dihydro-1H-pyrrole (195 mg, 1.22 mmol) and ZnI₂ (41 mg, 0.13 mmol) in DCM (50 mL). Mild exotherm and gas evolution occurred during the addition. The reaction was stirred at room temperature for 1 h then quenched with H₂O and brine. The aqueous layer was extracted with EtOAc. The combined organic layers were dried over Na₂SO₄, filtered, and the filtrate concentrated under reduced pressure to give crude product. The crude oil was purified via FCC on silica (5% EtOAc in hexane) to afford the title compound (256 mg, 75% yield). MS (ESI): mass calcd. for C₂₀H₂₃N, 277.2; m/z found, 278.1 [M+H]⁺. ¹H NMR (500 MHz, DMSO-d₆) δ 7.36-7.28 (m, 5H), 7.06-7.04 (d, J=8.1 Hz, 2H), 6.96-6.94 (d, J=8.2 Hz, 2H), 3.61 (s, 2H), 3.02-3.0 (d, J=8.9 Hz, 2H), 2.55-2.51 (m, 2H), 2.46-2.40 (br s, 2H), 2.21 (t, J=3.3 Hz, 1H), 1.64 (s, 2H), 1.13 (t, J=7.6 Hz, 3H).

Step C: (1R,5S,6s)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane. (1R,5S,6s)-3-Benzyl-6-(4-ethylphenyl)-3-azabicyclo[3.1.0]hexane (50 mg, 0.18 mmol) was taken up in EtOH (1.8 mL). 10% Pd/C (19 mg, 0.02 mmol) was added and the reaction vessel was evacuated and left under a H₂ balloon to stir at rt for 16 h. The reaction mixture was filtered through Celite® with MeOH and concentrated under reduced pressure. The title compound was used without further purification in the next step. MS (ESI): mass calcd. for C₁₃H₁₇N, 187.1; m/z found, 188.1 [M+H]⁺.

Step D: (2s,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. (1R,5S,6s)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane (16 mg, 0.085 mmol) and (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 16 mg, 0.094 mmol) were taken up in DMF (0.6 mL). DIPEA (37 μL, 0.214 mmol) and HATU (37 mg, 0.094 mmol) were added and the reaction was stirred at rt for 2 h. The reaction mixture was filtered through a PTFE filter with MeOH and purified via reverse phase HPLC (5-95% ACN in 20 mM NH₄OH in water) to afford the title compound (12 mg, 41% yield). MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.14-7.08 (m, 2H), 6.97-6.91 (m, 2H), 6.31 (s, 1H), 4.36 (s, 2H), 3.97 (d, J=12.2 Hz, 1H), 3.65 (t, J=2.1 Hz, 2H), 3.56 (dd, J=12.1, 3.7 Hz, 1H), 2.87 (tt, J=8.4, 7.2 Hz, 1H), 2.71-2.56 (m, 4H), 2.53-2.43 (m, 2H), 1.91-1.83 (m, 2H), 1.61 (t, J=3.6 Hz, 1H), 1.21 (t, J=7.6 Hz, 3H).

Example 87: (2r,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 86 using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step D. MS (ESI): mass calcd. for C₂₁H₂₆N₂O₂, 338.2; m/z found, 339.3 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.14-7.08 (m, 2H), 6.97-6.90 (m, 2H), 6.22 (s, 1H), 3.96 (d, J=12.2 Hz, 1H), 3.71-3.58 (m, 2H), 3.52 (dd, J=12.1, 4.0 Hz, 1H), 2.89 (p, J=8.2 Hz, 1H), 2.65-2.46 (m, 4H), 2.43-2.31 (m, 4H), 2.26-2.17 (m, 2H), 1.90-1.81 (m, 2H), 1.60 (t, J=3.5 Hz, 1H), 1.21 (t, J=7.6 Hz, 3H).

Example 88: (2s,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 86 using 3,4-dimethylbenzaldehyde instead of 4-ethylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.03 (d, J=7.7 Hz, 1H), 6.81 (d, J=2.0 Hz, 1H), 6.75 (dd, J=7.8, 2.0 Hz, 1H), 6.26 (s, 1H), 4.36 (s, 2H), 3.96 (d, J=12.2 Hz, 1H), 3.64 (t, J=2.4 Hz, 2H), 3.55 (dd, J=12.2, 3.6 Hz, 1H), 2.87 (tt, J=8.5, 7.2 Hz, 1H), 2.70-2.58 (m, 2H), 2.52-2.42 (m, 2H), 2.22 (s, 3H), 2.22 (s, 3H), 1.86 (q, J=3.1 Hz, 2H), 1.58 (t, J=3.5 Hz, 1H).

Example 89: (2r,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 86 using 3,4-dimethylbenzaldehyde instead of 4-ethylbenzaldehyde in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step D. MS (ESI): mass calcd. for C₂₁H₂₆N₂O₂, 338.2; m/z found, 339.2 [M+H]⁺. ¹H NMR (500 MHz, Chloroform-d) δ 7.02 (d, J=7.7 Hz, 1H), 6.80 (d, J=1.9 Hz, 1H), 6.75 (dd, J=7.8, 2.0 Hz, 1H), 6.32 (s, 1H), 3.95 (d, J 12.2 Hz, 1H), 3.67 (d, J=10.1 Hz, 1H), 3.62 (dd, J=10.2, 3.8 Hz, 1H), 3.52 (dd, J=12.1, 4.1 Hz, 1H), 2.89 (p, J=8.3 Hz, 1H), 2.58-2.47 (m, 2H), 2.41-2.30 (m, 4H), 2.23-2.18 (m, 8H), 1.88-1.81 (m, 2H), 1.57 (t, J=3.5 Hz, 1H).

Example 90: (2s,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 86 using 4-isopropylbenzaldehyde instead of 4-ethylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.16-7.11 (m, 2H), 6.98-6.93 (m, 2H), 6.30 (s, 1H), 4.36 (s, 2H), 3.96 (d, J=12.2 Hz, 1H), 3.68-3.61 (m, 2H), 3.56 (dd, J=12.2, 3.6 Hz, 1H), 2.92-2.80 (m, 2H), 2.70-2.60 (m, 2H), 2.53-2.43 (m, 2H), 1.92-1.84 (m, 2H), 1.61 (t, J=3.6 Hz, 1H), 1.22 (d, J=6.9 Hz, 6H).

Example 91: (2r,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 86 using 4-isopropylbenzaldehyde instead of 4-ethylbenzaldehyde in Step A and using (2r,4s)-6-oxo-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 4) instead of (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3) in Step D. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₂, 352.2; m/z found, 353.3 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.16-7.11 (m, 2H), 6.97-6.93 (m, 2H), 6.17 (s, 1H), 3.96 (d, J=12.1 Hz, 1H), 3.70-3.59 (m, 2H), 3.53 (dd, J=12.2, 4.0 Hz, 1H), 2.94-2.81 (m, 2H), 2.58-2.47 (m, 2H), 2.44-2.31 (m, 4H), 2.25-2.17 (m, 2H), 1.90-1.81 (m, 2H), 1.60 (t, J=3.5 Hz, 1H), 1.22 (d, J=6.9 Hz, 6H).

Example 92: (2s,4S)-2-((1R,5S,6S)-6-(2,3-Dihydro-1H-inden-5-yl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 86 using 2,3-dihydro-1H-indene-5-carbaldehyde instead of 4-ethylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₁H₂₄N₂O₃, 352.2; m/z found, 353.1 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.12 (d, J=7.6 Hz, 1H), 6.89 (d, J=1.7 Hz, 1H), 6.80 (dd, J=7.7, 1.7 Hz, 1H), 6.41 (s, 1H), 4.36 (s, 2H), 3.96 (d, J=12.2 Hz, 1H), 3.65 (t, J=2.1 Hz, 2H), 3.55 (dd, J=12.2, 3.5 Hz, 1H), 2.86 (td, J=7.4, 3.7 Hz, 5H), 2.71-2.59 (m, 2H), 2.53-2.41 (m, 2H), 2.05 (p, J=7.4 Hz, 2H), 1.90-1.83 (m, 2H), 1.61 (t, J=3.6 Hz, 1H).

Example 93: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 86 using 3-tert-butylbenzaldehyde instead of 4-ethylbenzaldehyde in Step A and using 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9) instead of 1-benzyl-2,5-dihydro-1H-pyrrole in Step B. MS (ESI): mass calcd. for C₂₃H₃₀N₂O₃, 382.2; m/z found, 383.3 [M+H]⁺. ¹H NMR (600 MHz, Chloroform-d) δ 7.25-7.20 (m, 2H), 7.13 (dt, J=7.6, 1.8 Hz, 1H), 6.92-6.88 (m, 1H), 5.91 (br s, 1H), 4.35 (d, J=9.4 Hz, 2H), 4.00 (dd, J=40.6, 11.9 Hz, 1H), 3.74-3.59 (m, 2H), 3.40 (dd, J=60.1, 9.9 Hz, 1H), 2.94-2.84 (m, 1H), 2.69-2.56 (m, 2H), 2.56-2.45 (m, 2H), 1.86-1.79 (m, 2H), 1.31 (s, 9H), 1.06 (s, 3H).

Example 94: (rac)-(2s,4s)-2-(1-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 5 using 1-bromo-4-ethylbenzene instead of 1-bromo-4-(tert-butyl)benzene in Step A. MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.21-7.06 (m, 4H), 6.16 (d, J=13.2 Hz, 1H), 4.35 (d, J=4.3 Hz, 2H), 4.23-3.94 (m, 1H), 3.85-3.55 (m, 3H), 2.93-2.81 (m, 1H), 2.70-2.59 (m, 4H), 2.54-2.39 (m, 2H), 1.94-1.82 (m, 1H), 1.22 (td, J=7.6, 1.5 Hz, 3H), 1.18-1.10 (m, 1H), 0.79-0.69 (m, 1H).

Example 95: (2r,4*S)-2-((1*R,5*S)-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 26 (Stationary phase: Whelk-O1 (S,S), 5 μm 250×21.2 mm, Mobile phase: 0.3% isopropylamine, 60% CO₂, 40% ACN/iPrOH (v/v 50/50)). MS (ESI): mass calcd. for C₂₃H₂₈N₂O₂, 364.2; m/z found, 365.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.23-7.16 (m, 2H), 7.15-7.05 (m, 2H), 6.15 (s, 1H), 4.23-3.91 (m, 1H), 3.85-3.51 (m, 3H), 2.94-2.84 (m, 1H), 2.57-2.45 (m, 2H), 2.44-2.28 (m, 4H), 2.26-2.15 (m, 2H), 1.91-1.80 (m, 1H), 1.39 (d, J=1.9 Hz, 3H), 1.12 (dt, J=9.0, 5.0 Hz, 1H), 0.87-0.79 (m, 2H), 0.77-0.68 (m, 3H).

Example 96: (2r,4*R)-2-((1*S,5*R)-1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 26 (Stationary phase: Whelk-O1 (S,S), 5 μm 250×21.2 mm, Mobile phase: 0.3% isopropylamine, 60% CO₂, 40% ACN/iPrOH (v/v 50/50)). MS (ESI): mass calcd. for C₂₃H₂₈N₂O₂, 364.2; m/z found, 365.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.25-7.16 (m, 2H), 7.13-7.05 (m, 2H), 6.10 (s, 1H), 4.23-3.91 (m, 1H), 3.86-3.52 (m, 3H), 2.94-2.84 (m, 1H), 2.57-2.45 (m, 2H), 2.44-2.30 (m, 4H), 2.26-2.16 (m, 2H), 1.91-1.80 (m, 1H), 1.39 (d, J=1.8 Hz, 3H), 1.12 (dt, J=9.1, 5.1 Hz, 1H), 0.87-0.79 (m, 2H), 0.77-0.68 (m, 3H).

Example 97: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: 4-Methyl-N′-(2-methylbenzylidene)benzenesulfonohydrazide. 4-Methylbenzenesulfonhydrazide (3.1 g, 16.6 mmol) was added to a solution of 2-methylbenzaldehyde (2.0 g, 16.6 mmol) in MeOH (40 mL). The reaction mixture was stirred for 16 hours at room temperature. The precipitate was collected by filtration and washed with chilled MeOH before drying under reduced pressure to afford the title compound as a white solid (3.7 g, 77% yield). MS (ESI): mass calcd. for C₁₅H₁₆N₂O₂S 288.1; m/z found, 289.1 [M+H]⁺.

Step B: (rac)-(1*R,5*S,6*R)-3-Benzyl-1-methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane. Benzyltriethylammonium chloride (237 mg, 1.04 mmol) was added to a mixture of 4-methyl-N-(2-methylbenzylidene)benzenesulfonohydrazide (1.0 g, 3.47 mmol) in aq. NaOH (15%, 8 mL) and toluene (8 mL). The reaction mixture was stirred vigorously at 80° C. for 1 hour. The toluene layer was separated, washed with sat. aq. NH₄Cl and brine, dried over anhydrous Na₂SO₄, and filtered to obtain 1-(diazomethyl)-2-methylbenzene in toluene (8 mL, crude). This solution was added dropwise over 30 minutes to a −10° C. mixture of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9, 500 mg, 2.89 mmol) and ZnI₂ (923 mg, 2.89 mmol) in DCM (30 mL). The reaction mixture was stirred at room temperature for 16 hours before being quenched with water and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to afford the crude product, which was purified by FCC (5-13% EtOAc in ether) to afford the title compound (480 mg, 60% yield). MS (ESI): mass calcd. for C₂₀H₂₃N, 277.2; m/z found, 278.2 [M+H]⁺.

Step C: (rac)-(1*R,5*S,6*R)-1-Methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane. (1*R,5*S,6*R)-3-Benzyl-1-methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane (430 mg, 1.55 mmol) and dry Pd/C (100 mg, 10 wt. %) were taken up in MeOH (8 mL) and THF (40 mL). The resultant mixture was stirred under H₂ (15 psi) at room temperature for 6 hours. The suspension was filtered through a pad of Celite® and the pad washed with MeOH. The filtrate was concentrated under reduced pressure to afford the title product as a yellow oil (370 mg, crude), which was carried on without further purification. MS (ESI): mass calcd. for C₁₃H₁₇N, 187.1; m/z found, 188.2 [M+H]⁺.

Step D: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. T₃P® (1.2 mL, 50% in ethyl acetate, 2.0 mmol) was added to a solution of (1*R,5*S,6*R)-1-methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane (360 mg, 1.9 mmol), (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 200 mg, 1.2 mmol), and DIPEA (1.2 mL, 6.8 mmol) in DCM (5 mL). The reaction was stirred at room temperature for 16 hours before being quenched with H₂O and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to afford the crude product, which was purified by RP-HPLC (40-70% (v/v) CH₃CN in H₂O with 0.05% NH₃+10 mM NH₄HCO₃) to afford the title compound as a white solid (148 mg, 36% yield). MS (ESI): mass calcd. for C₂₀H₂₄N₂O₃, 340.2; m/z found, 341.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.22-7.10 (m, 3H), 7.07-6.98 (m, 1H), 6.16-6.04 (m, 1H), 4.38 (d, J=7.3 Hz, 2H), 4.08-3.93 (m, 1H), 3.79-3.62 (m, 2H), 3.51-3.38 (m, 1H), 2.96-2.84 (m, 1H), 2.72-2.60 (m, 2H), 2.56-2.45 (m, 2H), 2.32-2.26 (m, 3H), 1.92-1.86 (m, 1H), 1.74-1.70 (m, 1H), 0.95 (s, 3H).

Example 98: (2s,4S)-2-((1R,5S,6S)-6-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 1-benzyl-2,5-dihydro-1H-pyrrole instead of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9) in Step B. MS (ESI): mass calcd. for C₁₉H₂₂N₂O₃, 326.2; m/z found, 327.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.22-7.08 (m, 3H), 7.00-6.91 (m, 1H), 6.53-6.28 (m, 1H), 4.47-4.33 (m, 2H), 4.01 (d, J=12.16 Hz, 1H), 3.73-3.66 (m, 2H), 3.60 (dd, J=4.53, 12.16 Hz, 1H), 2.98-2.84 (m, 1H), 2.75-2.60 (m, 2H), 2.56-2.46 (m, 2H), 2.37 (s, 3H), 1.98-1.92 (m, 1H), 1.91-1.86 (m, 1H), 1.65 (t, J=3.81 Hz, 1H).

Example 99: (2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 93 (Stationary phase: OD-H, 2×25 cm, Mobile phase: 0.1% TEA, 60% CO₂, 40% heptane/iPrOH (v/v 50/50)). MS (ESI): mass calcd. for C₂₃H₃₀N₂O₃, 382.2; m/z found, 383.2 [M+H]⁺. ¹H NMR (600 MHz, Chloroform-d) δ 7.25-7.20 (m, 2H), 7.16-7.10 (m, 1H), 6.93-6.87 (m, 1H), 5.97-5.91 (m, 1H), 4.36 (s, 1H), 4.35 (s, 1H), 4.00 (dd, J=40.6, 12.0 Hz, 1H), 3.73-3.59 (m, 2H), 3.40 (dd, J=61.4, 11.0 Hz, 1H), 2.95-2.84 (m, 1H), 2.68-2.57 (m, 2H), 2.55-2.45 (m, 2H), 1.85-1.79 (m, 2H), 1.31 (s, 9H), 1.05 (s, 3H).

Example 100: (2s,4*R)-2-((1*S,5*R,6*S)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 93 (Stationary phase: OD-H, 2×25 cm, Mobile phase: 0.1% TEA, 60% CO₂, 40% heptane/iPrOH (v/v 50/50)). MS (ESI): mass calcd. for C₂₃H₃₀N₂O₃, 382.2; m/z found, 383.2 [M+H]⁺. ¹H NMR (600 MHz, Chloroform-d) δ 7.25-7.20 (m, 2H), 7.16-7.10 (m, 1H), 6.93-6.87 (m, 1H), 5.97-5.91 (m, 1H), 4.36 (s, 1H), 4.35 (s, 1H), 4.00 (dd, J=40.6, 12.0 Hz, 1H), 3.73-3.59 (m, 2H), 3.40 (dd, J=61.4, 11.0 Hz, 1H), 2.95-2.84 (m, 1H), 2.68-2.57 (m, 2H), 2.55-2.45 (m, 2H), 1.85-1.79 (m, 2H), 1.31 (s, 9H), 1.05 (s, 3H).

Example 101: (2s,4S)-2-((1R,5S,6S)-6-(3-Isobutylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 3-isobutylbenzaldehyde (Intermediate 10) instead of 2-methylbenzaldehyde in Step A and 1-benzyl-2,5-dihydro-1H-pyrrole instead of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9) in Step B. MS (ESI): mass calcd. for C₂₂H₂₈N₂O₃, 368.2; m/z found, 369.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.22-7.14 (m, 1H), 6.97 (d, J=7.5 Hz, 1H), 6.87-6.79 (m, 2H), 6.48 (s, 1H), 4.37 (s, 2H), 3.99 (d, J=12.0 Hz, 1H), 3.71-3.63 (m, 2H), 3.57 (dd, J=3.5, 12.3 Hz, 1H), 2.94-2.82 (m, 1H), 2.74-2.61 (m, 2H), 2.55-2.40 (m, 4H), 1.94-1.82 (m, 3H), 1.64-1.60 (m, 1H), 0.90 (d, J=6.5 Hz, 6H).

Example 102: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3,4-Dimethylphenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 3,4-dimethylbenzaldehyde instead of 2-methylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₁H₂₆N₂O₃, 354.2; m/z found, 355.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.06 (d, J=7.6 Hz, 1H), 6.90 (s, 1H), 6.86-6.81 (m, 1H), 5.98 (br s, 1H), 4.36 (d, J=6.3 Hz, 2H), 4.03-3.92 (m, 1H), 3.74-3.57 (m, 2H), 3.46-3.32 (m, 1H), 2.95-2.84 (m, 1H), 2.70-2.57 (m, 2H), 2.57-2.44 (m, 2H), 2.30-2.20 (m, 6H), 1.83-1.73 (m, 2H), 1.05 (s, 3H).

Example 103: (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl-5-D)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: (1R,5S,6s)-3-Benzyl-6-(3-(tert-butyl)-5-iodophenyl)-3-azabicyclo[3.1.0]hexane. The title compound was prepared in a manner analogous to Example 86, Steps A and B using 3-tert-butyl-5-iodobenzaldehyde (Intermediate 13) instead of 4-ethylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₂H₂₆IN, 431.1; m/z found, 432.1 [M+H]⁺.

Step B: (1R,5S,6s)-6-(3-(tert-Butyl)-5-iodophenyl)-3-azabicyclo[3.1.0]hexane. (1R,5S,6s)-3-Benzyl-6-(3-(tert-butyl)-5-iodophenyl)-3-azabicyclo[3.1.0]hexane (23 g, 53.3 mmol) and TEA (22 mL, 160 mmol) were taken up in DCM (460 mL) under N₂ and cooled to 5° C. To this was added dropwise 1-chloroethyl carbonochloridate (23 g, 160 mmol) and the resulting solution was stirred for 30 min at room temperature. The reaction mixture was concentrated under reduced pressure and diluted in MeOH (230 mL). The reaction was stirred for an additional 30 min while heating at reflux. After cooling to rt, the mixture was concentrated under reduced pressure and purified by RP-HPLC to provide the title compound as a white solid (4.6 g, 25% yield).

Step C: (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)-5-iodophenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 2.54 g, 14.8 mmol), DMF (100 mL), DIPEA (5.9 mL, 33.7 mmol), HATU (5.38 g, 14.2 mmol), and (1R,5S,6s)-6-(3-(tert-butyl)-5-iodophenyl)-3-azabicyclo[3.1.0]hexane (4.60 g, 13.5 mmol) were combined under N₂. The resulting solution was stirred for 1 h at room temperature then quenched with ice water. The solids were collected by filtration to provide the title compound as a white solid (4.8 g, 72% yield). MS (ESI): mass calcd. for C₂₂H₂₇IN₂O₃, 494.1; m/z found, 495.2 [M+H]⁺. ¹H NMR (300 MHz, DMSO-d₆) δ 8.08 (s, 1H), 7.47 (t, J=1.6 Hz, 1H), 7.20 (t, J=1.6 Hz, 1H), 7.14 (t, J=1.7 Hz, 1H), 4.37 (s, 2H), 3.76 (dd, J=18.9, 11.2 Hz, 2H), 3.55 (dd, J=10.5, 4.1 Hz, 1H), 3.51-3.32 (m, 1H), 2.88 (p, J=8.8 Hz, 1H), 2.52-2.32 (m, 4H), 1.99 (dt, J=7.4, 3.7 Hz, 1H), 1.91 (dt, J=7.4, 3.7 Hz, 1H), 1.64 (t, J=3.5 Hz, 1H), 1.24 (s, 9H).

Step D: (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl-5-D)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one.

Method A: (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)-5-iodophenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one (150 mg, 0.303 mmol) was taken up in CD₃OD (70 mL) and D-THF (2 mL). This solution was passed through an H-Cube® reactor once (10% Pd/C, 1 mL/min, 1 bar) using D₂O to generate D₂. The recovered solution was concentrated under reduced pressure. Analysis of the crude material by ¹H NMR indicated approximately 93% deuterium incorporation. The crude product was purified via FCC (9/1 EtOAc/hexane) to provide the title compound (75 mg, 67% yield).

Method B: (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)-5-iodophenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one (20 mg, 0.0404 mmol) was taken up in THF (20 mL) and CD₃OD (10 mL) then concentrated under reduced pressure at rt. This was repeated once more before the residue was taken up in CD₃OD (20 mL). To this was added Pd/C (30 mg, 10 wt. %) that had been taken up in D₂O and CD₃OD (1:1, 10 mL) and stirred 5 min before filtering off the liquid portion. This was stirred at rt under an atmosphere of D₂ for 6 h. The reaction solution was filtered, and the filtrate was concentrated under reduced pressure at rt. This procedure was repeated seven times. The combined crude product was purified by RP-HPLC (35-65% ACN in water with 0.05% TFA modifier) to provide the title compound as a light yellow solid (54 mg, 52% yield). MS (ESI): mass calcd. for C₂₂H₂₇DN₂O₃, 369.2; m/z found, 370.2 [M+H]⁺. ¹H NMR (500 MHz, Methanol-d₄) δ 7.21-7.17 (m, 1H), 7.13 (t, J=1.9 Hz, 1H), 6.84-6.81 (m, 1H), 4.48 (s, 2H), 3.88 (d, J=12.1 Hz, 1H), 3.79 (d, J=10.6 Hz, 1H), 3.68 (dd, J=10.5, 4.3 Hz, 1H), 3.51 (dd, J=12.0, 4.5 Hz, 1H), 3.04-2.96 (m, 1H), 2.60-2.51 (m, 2H), 2.51-2.43 (m, 2H), 1.99-1.92 (m, 1H), 1.94-1.87 (m, 1H), 1.63 (t, J=3.6 Hz, 1H), 1.30 (s, 9H).

Example 104: (2s,4S)-2-((1R,5S,6S)-6-(3-(1-Hydroxy-2-methylpropan-2-yl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: (1R,5S,6s)-3-Benzyl-6-(3-bromophenyl)-3-azabicyclo[3.1.0]hexane. The title compound was prepared in a manner analogous to Example 97, Steps A and B using 3-bromobenzaldehyde instead of 2-methylbenzaldehyde in Step A and 1-benzyl-2,5-dihydro-1H-pyrrole instead of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9) in Step B. MS (ESI): mass calcd. for C₁₈H₁₈BrN, 327.1; m/z found, 328.1 [M+H]⁺.

Step B: Methyl 2-(3-((1R,5S,6s)-3-benzyl-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropanoate. (1R,5S,6s)-3-Benzyl-6-(3-bromophenyl)-3-azabicyclo[3.1.0]hexane (1.8 g, 5.5 mmol), ((1-methoxy-2-methylprop-1-en-1-yl)oxy)trimethylsilane (1.9 g, 11.0 mmol), and ZnF₂ (0.17 g, 1.6 mmol) were dissolved in DMF (20 mL). The resultant mixture was sparged with N₂ for 5 minutes and then treated with P(t-Bu)₃ (3.7 g, 2.7 mmol) and Pd₂(dba)₃ (1.0 g, 1.1 mmol). The resultant mixture was sparged with N₂ for 5 minutes and then stirred while heating at 90° C. for 6 hours. After cooling to room temperature, the reaction was quenched with H₂O and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to give the crude product, which was purified by FCC (9-25% EtOAc in ether) to afford the title compound (350 mg, 18% yield). MS (ESI): mass calcd. for C₂₃H₂₇NO₂, 349.2; m/z found, 350.2 [M+H]⁺.

Step C: 2-(3-((1R,5S,6s)-3-Benzyl-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropan-1-ol. LiAlH₄ (65 mg, 1.7 mmol) was added to a −50° C. solution of methyl 2-(3-((1R,5S,6s)-3-benzyl-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropanoate (300 mg, 0.86 mmol) in THF (10 mL). The resultant mixture was stirred at −50° C. for 3 hours before slowly quenching with H₂O (0.1 mL) and NaOH (15% in water, 0.1 mL). The resultant mixture was stirred at room temperature for 30 minutes before additional H₂O (0.3 mL) was added. This was stirred at room temperature for 30 minutes then dried over anhydrous MgSO₄. The suspension was filtered through a pad of Celite® and the pad washed with ethyl acetate. The filtrate was concentrated under reduced pressure to give the crude product (280 mg, quant.), which was used in the next step without further purification. MS (ESI): mass calcd. for C₂₂H₂₇NO, 321.2; m/z found, 322.2 [M+H]⁺.

Step D: 2-(3-((1R,5S,6s)-3-Azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropan-1-ol. 2-(3-((1R,5S,6s)-3-Benzyl-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropan-1-ol (280 mg, 0.871 mmol) and dry Pd/C (150 mg, 10 wt %) were taken up in a mixture of THF:MeOH (5:1, 18 mL). The resultant mixture was stirred at room temperature for 5 hours under H₂ (15 psi). The suspension was filtered through a pad of Celite® and the pad washed with THF. The filtrate was concentrated under reduced pressure to afford the title product (200 mg, crude), which was used in the next step without further purification.

Step E: (2s,4S)-2-((1R,5S,6S)-6-(3-(1-Hydroxy-2-methylpropan-2-yl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. T₃P® (825 mg, 50% in ethyl acetate, 1.30 mmol) was added to a solution of 2-(3-((1R,5S,6s)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropan-1-ol (200 mg, 0.865 mmol), (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 163 mg, 0.952 mmol), and Et₃N (0.36 mL, 2.59 mmol) in DCM (10 mL). The mixture was stirred at room temperature for 3 hours before being quenched with H₂O and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to give the crude product, which was purified by RP-HPLC (22-52% (v/v) CH₃CN in H₂O with 0.05% ammonium hydroxide) to afford the title compound as a white solid (46.5 mg, 14% yield). MS (ESI): mass calcd. for C₂₂H₂₈N₂O₄, 384.2; m/z found, 385.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 8.09 (s, 1H), 7.22-7.07 (m, 3H), 6.85-6.75 (m, 1H), 4.62 (t, J=5.4 Hz, 1H), 4.43-4.32 (m, 2H), 3.77-3.66 (m, 2H), 3.59-3.52 (m, 1H), 3.41-3.36 (m, 3H), 2.95-2.84 (m, 1H), 2.44-2.29 (m, 4H), 1.97-1.79 (m, 2H), 1.65-1.57 (m, 1H), 1.19 (s, 6H).

Example 105: 2-Methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carbonyl)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoic acid

Step A: Methyl 2-(3-((1R,5S,6s)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropanoate. Methyl 2-(3-((1R,5S,6s)-3-benzyl-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropanoate (from Example 104, Step B) (330 mg, 0.944 mmol) and dry Pd/C (100 mg, 10 wt %) were taken up in a mixture of THF:MeOH (10:1, 22 mL). The resultant mixture was stirred under H₂ (15 psi) at room temperature for 16 hours. The suspension was filtered through a pad of Celite® and the pad washed with THF. The filtrate was concentrated under reduced pressure to afford the title product (250 mg, quant.), which was used in the next step without further purification. MS (ESI): mass calcd. for C₁₆H₂₁NO₂, 259.2; m/z found, 260.2 [M+H]⁺.

Step B: Methyl 2-methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carbonyl)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoate. T₃P® (920 mg, 50% in ethyl acetate, 1.45 mmol) was added to a solution of methyl 2-(3-((1R,5S,6s)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)-2-methylpropanoate (250 mg, 0.964 mmol), (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 165 mg, 0.964 mmol), and Et₃N (0.40 mL, 2.90 mmol) in DCM (10 mL). The mixture was stirred at room temperature for 3 hours before being quenched with H₂O and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to give the crude product (300 mg, 76% yield), which was used in the next step without further purification. MS (ESI): mass calcd. for C₂₃H₂₈N₂O₅, 412.2; m/z found, 413.2 [M+H]⁺.

Step C: 2-Methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carbonyl)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoic acid. LiOH.H₂O (131 mg, 3.12 mmol) was added to a solution of methyl 2-methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carbonyl)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoate (280 mg, 0.679 mmol) in 1,4-dioxane (5 mL) and H₂O (5 mL). The resulting mixture was stirred at room temperature for 16 hours before being quenched with H₂O and washed with ethyl acetate. The aqueous phase was separated, adjusted to pH 5-6 with 1 M HCl, and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to give the crude product, which was purified by RP-HPLC (16-56% (v/v) CH₃CN in H₂O with 0.225% HCOOH). Further purification by SFC (DAICEL CHIRALPAK AS 250 mm×30 mm, 10 μm; isocratic elution: 30-70% EtOH (containing 0.1% of 25% aq. NH₃) in supercritical CO₂ (v/v)) afforded the title compound as a white solid (26 mg, 20% yield). MS (ESI): mass calcd. for C₂₂H₂₆N₂O₅, 398.2; m/z found, 399.1 [M+H]⁺. ¹H NMR (400 MHz, DMSO-d₆) δ 12.27 (br s, 1H), 8.09 (s, 1H), 7.24-7.17 (m, 1H), 7.13-7.05 (m, 2H), 6.90-6.83 (m, 1H), 4.40-4.33 (m, 2H), 3.78-3.65 (m, 2H), 3.58-3.51 (m, 1H), 3.39-3.38 (m, 1H), 2.95-2.83 (m, 1H), 2.44-2.26 (m, 4H), 1.96-1.80 (m, 2H), 1.67-1.61 (m, 1H), 1.44 (s, 6H).

Example 106: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 3-(trifluoromethyl)benzaldehyde instead of 2-methylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.2; m/z found, 395.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.51-7.46 (m, 1H), 7.45-7.40 (m, 1H), 7.39-7.35 (m, 1H), 7.34-7.28 (m, 1H), 6.36-6.27 (m, 1H), 4.37 (d, J=6.0 Hz, 2H), 4.07-3.97 (m, 1H), 3.77-3.61 (m, 2H), 3.50-3.34 (m, 1H), 2.94-2.83 (m, 1H), 2.72-2.61 (m, 2H), 2.55-2.44 (m, 2H), 1.93-1.86 (m, 2H), 1.07-1.03 (m, 3H).

Example 107: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 4-(trifluoromethoxy)benzaldehyde instead of 2-methylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.19-7.11 (m, 4H), 6.39-6.23 (m, 1H), 4.37 (d, J=5.84 Hz, 2H), 4.07-3.94 (m, 1H), 3.76-3.60 (m, 2H), 3.50-3.31 (m, 1H), 2.94-2.84 (m, 1H), 2.72-2.61 (m, 2H), 2.55-2.43 (m, 2H), 1.87-1.78 (m, 2H), 1.05 (s, 3H).

Example 108: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(4-Cyclopropylphenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 4-cyclopropylbenzaldehyde instead of 2-methylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₂H₂₆N₂O₃, 366.2; m/z found, 367.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.09-6.91 (m, 4H), 6.56-6.31 (m, 1H), 4.37 (d, J=6.02 Hz, 2H), 4.04-3.89 (m, 1H), 3.76-3.57 (m, 2H), 3.48-3.29 (m, 1H), 2.95-2.79 (m, 1H), 2.75-2.61 (m, 2H), 2.56-2.29 (m, 2H), 1.89-1.84 (m, 1H), 1.82-1.76 (m, 2H), 1.03 (s, 3H), 0.98-0.89 (m, 2H), 0.72-0.61 (m, 2H).

Example 109: (2s,4S)-2-((1R,5S,6S)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: tert-Butyl (1R,5S,6s)-6-(4-cyclopropyl-2-methylphenyl)-2,4-dioxo-3-azabicyclo[3.1.0]hexane-3-carboxylate. The title compound was prepared in a manner analogous to Example 78, Steps A and B using 4-cyclopropyl-2-methylbenzaldehyde (Intermediate 12) instead of 3-tert-butylbenzaldehyde in Step A and tert-butyl 2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carboxylate instead of N-benzylmaleimide in Step B. ¹H NMR (300 MHz, CDCl₃) δ 7.21 (d, J=8.3 Hz, 1H), 6.95 (s, 1H), 6.84 (s, 1H), 2.87 (t, J=3.1 Hz, 1H), 2.72 (d, J=3.2 Hz, 2H), 2.40 (s, 3H), 1.90-1.82 (m, 1H), 1.57 (s, 9H), 0.96-0.90 (m, 2H), 0.68-0.61 (m, 2H).

Step B: (1R,5S,6s)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-2,4-dione. tert-Butyl (1R,5S,6s)-6-(4-cyclopropyl-2-methylphenyl)-2,4-dioxo-3-azabicyclo[3.1.0]hexane-3-carboxylate (560 mg, 1.64 mmol) was taken up in DCM (7 mL) and cooled to 0° C. To this was added TFA (1.5 mL, 19.7 mmol) and the mixture was stirred at rt for 1 h before being concentrated under reduced pressure. The crude product was purified by FCC (0-65% EtOAc in heptane) to yield the title compound as a white solid (209 mg, 53% yield). ¹H NMR (300 MHz, CDCl₃) δ 7.51 (br s, 1H), 6.91 (s, 1H), 6.85 (s, 2H), 2.90 (t, J=3.0 Hz, 1H), 2.71 (d, J=1.5 Hz, 2H), 2.40 (s, 3H), 1.94-1.77 (m, 1H), 0.99-0.88 (m, 2H), 0.66 (d, J=5.0 Hz, 2H).

Step C: (1R,5S,6s)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane. (1R,5S,6s)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-2,4-dione (209 mg, 0.866 mmol) was taken up in anhydrous THF (5 mL). NaBH₄ (72.1 mg, 1.91 mmol) was added and this was stirred at rt for 15 min. BF₃.OEt₂ (0.29 mL, 2.34 mmol) was added dropwise and the mixture was heated at 50° C. for 16 h. Additional NaBH₄ (32.7 mg, 0.866 mmol) was added and the mixture was stirred at rt for 15 min. Then, BF₃.OEt₂ (0.11 mL, 0.866 mmol) was added and the mixture was stirred at 50° C. for 3 h. The reaction was cooled to 0° C. and water was added dropwise. Finally, MeOH (15 mL) was added and the mixture was stirred at 100° C. for 16 h. The mixture was concentrated under reduced pressure and purified by FCC (0-80% DCM/MeOH (9:1) in DCM) to yield the title compound as a white solid (185 mg, quant.).

Step D: (2s,4S)-2-((1R,5S,6S)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. (1R,5S,6s)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane (185 mg, 0.866 mmol) and (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 179 mg, 1.04 mmol) were taken up in DMF (5 mL). To this was added T₃P® (0.67 mL, 50% in EtOAc, 1.13 mmol) and DIPEA (0.45 mL, 2.60 mmol). The mixture was stirred at rt for 1 h. Sat. aq. NaHCO₃ was added and the mixture was extracted with EtOAc. The organic layers were dried over MgSO₄, filtered, and concentrated under reduced pressure. The crude product was purified by FCC (0-30% DCM/MeOH (20:1) in DCM) to yield the title compound as a white foam (93 mg, 94% yield). MS (ESI): mass calcd. for C₂₂H₂₆N₂O₃, 366.2; m/z found, 367.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 6.88 (s, 1H), 6.86-6.79 (m, 2H), 6.23 (s, 1H), 4.36 (s, 2H), 3.98 (d, J=12.2 Hz, 1H), 3.70-3.62 (m, 2H), 3.57 (dd, J=12.2, 4.5 Hz, 1H), 2.92-2.84 (m, 1H), 2.71-2.58 (m, 2H), 2.53-2.44 (m, 2H), 2.32 (s, 3H), 1.92-1.87 (m, 1H), 1.86-1.78 (m, 2H), 1.58 (t, J=3.8 Hz, 1H), 0.96-0.87 (m, 2H), 0.67-0.61 (m, 2H).

Example 110: (2s,4S)-2-((1R,5S,6S)-6-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 109 using 3-chloro-4-methylbenzaldehyde instead of 4-cyclopropyl-2-methylbenzaldehyde (Intermediate 12) in Step A. MS (ESI): mass calcd. for C₁₉H₂₁ClN₂O₃, 360.1; m/z found, 361.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.11 (d, J=7.9 Hz, 1H), 6.99 (d, J=1.7 Hz, 1H), 6.82 (dd, J=7.8, 1.8 Hz, 1H), 6.10 (s, 1H), 4.36 (s, 2H), 3.97 (d, J=12.3 Hz, 1H), 3.69-3.61 (m, 2H), 3.55 (dd, J=12.3, 3.5 Hz, 1H), 2.93-2.82 (m, 1H), 2.69-2.58 (m, 2H), 2.55-2.43 (m, 2H), 2.32 (s, 3H), 1.92-1.83 (m, 2H), 1.59 (t, J=3.5 Hz, 1H).

Example 111: (2s,4S)-2-((1R,5S,6S)-6-(3-Ethyl-4-fluorophenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 3-ethyl-4-fluorobenzaldehyde (Intermediate 11) instead of 2-methylbenzaldehyde in Step A and 1-benzyl-2,5-dihydro-1H-pyrrole instead of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9) in Step B. MS (ESI): mass calcd. for C₂₀H₂₃FN₂O₃, 358.2; m/z found, 359.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 6.95-6.84 (m, 2H), 6.82-6.76 (m, 1H), 6.08 (br s, 1H), 4.37 (s, 2H), 3.98 (d, J=12.2 Hz, 1H), 3.69-3.63 (m, 2H), 3.59-3.52 (m, 1H), 2.94-2.84 (m, 1H), 2.69-2.59 (m, 4H), 2.56-2.45 (m, 2H), 1.90-1.83 (m, 2H), 1.62-1.59 (m, 1H), 1.22 (t, J=7.6 Hz, 3H).

Example 112: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 4-methyl-3-(trifluoromethyl)benzaldehyde instead of 2-methylbenzaldehyde in Step A. MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₃, 408.2; m/z found, 409.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.38-7.32 (m, 1H), 7.24-7.13 (m, 2H), 6.24-6.13 (m, 1H), 4.37 (d, J=6.0 Hz, 2H), 4.00 (dd, J=12.0, 20.0 Hz, 1H), 3.76-3.59 (m, 2H), 3.49-3.33 (m, 1H), 2.94-2.83 (m, 1H), 2.72-2.59 (m, 2H), 2.56-2.41 (m, 5H), 1.90-1.79 (m, 2H), 1.09-0.99 (m, 3H).

Example 113: (2s,4S)-2-((1R,5S,6S)-6-(2-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 97 using 2-methyl-3-(trifluoromethyl)benzaldehyde instead of 2-methylbenzaldehyde in Step A and 1-benzyl-2,5-dihydro-1H-pyrrole instead of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9) in Step B. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.2; m/z found, 395.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.54-7.49 (m, 1H), 7.25-7.19 (m, 2H), 6.06 (br s, 1H), 4.38 (s, 2H), 4.07-4.02 (m, 1H), 3.76-3.68 (m, 2H), 3.65-3.59 (m, 1H), 2.96-2.87 (m, 1H), 2.70-2.60 (m, 2H), 2.56-2.47 (m, 5H), 1.99-1.88 (m, 2H), 1.71-1.67 (m, 1H).

Example 114: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: N-(4-Bromo-3-(trifluoromethoxy)benzylidene)-4-methylbenzenesulfonohydrazide. 4-Methylbenzenesulfonohydrazide (1.7 g, 9.29 mmol) was added to a solution of 4-bromo-3-(trifluoromethoxy)benzaldehyde (2.5 g, 9.29 mmol) in MeOH (50 mL). The reaction mixture was stirred for 16 hours at room temperature and then cooled to −10° C. The precipitate was collected by filtration and washed with cold MeOH before drying under reduced pressure to afford the title compound as a white solid (3.2 g, 78% yield), which was carried on without further purification. ¹H NMR (400 MHz, DMSO-d₆) δ 11.75 (br s, 1H), 7.92 (s, 1H), 7.86-7.81 (m, 1H), 7.79-7.72 (m, 2H), 7.66 (s, 1H), 7.57-7.50 (m, 1H), 7.43-7.36 (m, 2H), 2.36 (s, 3H).

Step B: (rac)-(1*R,5*S,6*R)-3-Benzyl-6-(4-bromo-3-(trifluoromethoxy)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane. Benzyltriethylammonium chloride (156 mg, 0.685 mmol) was added to a mixture of N-(4-bromo-3-(trifluoromethoxy)benzylidene)-4-methylbenzenesulfonohydrazide (1.0 g, 2.30 mmol) in aq. NaOH (15%, 8 mL) and toluene (8 mL). The reaction mixture was stirred vigorously at 80° C. for 1 hour before cooling to room temperature. The toluene layer was separated, washed with sat. aq. NH₄Cl and brine, dried over anhydrous Na₂SO₄, and filtered to obtain 1-bromo-4-(diazomethyl)-2-(trifluoromethoxy)benzene (8 mL in toluene, crude). This was added dropwise over 30 minutes to a −10° C. mixture of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9, 400 mg, 2.31 mmol) and ZnI₂ (737 mg, 2.31 mmol) in DCM (30 mL). The reaction mixture was stirred room temperature for 16 hours before being quenched with water and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to give the crude product, which was purified by FCC (0-13% EtOAc in ether) to afford the title compound as a yellow oil (187 mg, 16% yield). MS (ESI): mass calcd. for C₂₀H₁₉BrF₃NO, 425.1; m/z found, 425.9 [M+H]⁺.

Step C: (rac)-(1*R,5*S,6*R)-3-Benzyl-1-methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane. (rac)-(1*R,5*S,6*R)-3-Benzyl-6-(4-bromo-3-(trifluoromethoxy)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane (167 mg, 0.392 mmol), 2,4,6-trimethyl-1,3,5,2,4,6-trioxatriborinane (148 mg, 1.18 mmol), and Cs₂CO₃ (383 mg, 1.18 mmol) were taken up in H₂O (2 mL) and 1,4-dioxane (8 mL). The mixture was sparged with N₂ for 5 minutes and then treated with Pd(dppf)Cl₂.CH₂Cl₂ (32 mg, 0.039 mmol). The resultant mixture was sparged with N₂ for 5 minutes and then stirred while heating under microwave irradiation at 120° C. for 1 hour before cooling to room temperature. The reaction mixture was concentrated under reduced pressure and purified by FCC (0-13% EtOAc in ether) to afford the title compound as a yellow oil (120 mg, 85% yield). MS (ESI): mass calcd. for C₂₁H₂₂F₃NO, 361.2; m/z found, 362.1 [M+H]⁺.

Step D: (rac)-(1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane. (rac)-(1*R,5*S,6*R)-3-Benzyl-1-methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane (100 mg, 0.277 mmol) and dry Pd/C (100 mg, 10 wt. %) were taken up in MeOH (2 mL) and THF (10 mL). The resultant mixture was stirred under H₂ (15 psi) at room temperature for 1 hour. The suspension was filtered through a pad of Celite® and the pad washed with MeOH. The filtrate was concentrated under reduced pressure to afford the title product as a yellow oil (90 mg, quant.), which was used in the next step without further purification. MS (ESI): mass calcd. for C₁₄H₁₆F₃NO, 271.1; m/z found, 272.1 [M+H]⁺.

Step E: (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. T₃P® (0.30 mL, 50% in ethyl acetate, 0.50 mmol) was added to a solution of (rac)-(1*R,5*S,6*R)-1-methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane (90 mg, 0.33 mmol), (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 56 mg, 0.33 mmol), and DIPEA (0.29 mL, 1.6 mmol) in DCM (10 mL). The reaction was stirred at room temperature for 16 hours before being quenched with H₂O and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to give the crude product, which was purified by RP-HPLC (40-70% (v/v) CH₃CN in H₂O with 0.05% NH₃+10 mM NH₄HCO₃) to afford the title compound as a pale solid (23 mg, 16% yield). MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₄, 424.2; m/z found, 425.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.17 (d, J=8.0 Hz, 1H), 6.99-6.92 (m, 2H), 6.00-5.91 (m, 1H), 4.36 (d, J=5.6 Hz, 2H), 4.06-3.94 (m, 1H), 3.75-3.57 (m, 2H), 3.48-3.32 (m, 1H), 2.94-2.83 (m, 1H), 2.69-2.57 (m, 2H), 2.56-2.45 (m, 2H), 2.29 (s, 3H), 1.83-1.79 (m, 2H), 1.05 (s, 3H).

Example 115: (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 114 using 1-benzyl-2,5-dihydro-1H-pyrrole instead of 1-benzyl-3-methyl-2,5-dihydro-1H-pyrrole (Intermediate 9) in Step B. MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₄, 410.1; m/z found, 411.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.18-7.10 (m, 1H), 6.90-6.80 (m, 2H), 6.15 (br s, 1H), 4.40-4.32 (m, 2H), 4.03-3.94 (m, 1H), 3.71-3.62 (m, 2H), 3.60-3.52 (m, 1H), 2.94-2.82 (m, 1H), 2.70-2.58 (m, 2H), 2.55-2.43 (m, 2H), 2.30-2.23 (m, 3H), 1.93-1.84 (m, 2H), 1.63-1.61 (m, 1H).

Example 116: (2s,4S)-2-((1R,5S,6R)-6-(6-(tert-Butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

Step A: tert-Butyl (1R,5S,6s)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate. TMEDA (1.42 mL, 9.47 mmol) was added to a solution of CrCl₂ (1.16 g, 9.44 mmol) in THF (30 mL). The resultant blue mixture was stirred at room temperature for 15 mins. tert-Butyl 2,5-dihydro-1H-pyrrole-1-carboxylate (200 mg, 1.18 mmol) in THF (10 mL) was added followed by a solution of 2-(dichloromethyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (500 mg, 2.37 mmol) and LiI (633 mg, 4.73 mmol) in THF (15 mL). The mixture was stirred at room temperature for 16 hours before being quenched with water and extracted with ethyl acetate. The combined organic layers were dried over Na₂SO₄, filtered, and concentrated under reduced pressure to afford the crude product, which was purified by FCC (0-5% EtOAc in ether) to give the product as colorless oil (300 mg, 82% yield). ¹H NMR (400 MHz, CDCl₃) δ 3.65-3.49 (m, 2H), 3.39-3.28 (m, 2H), 1.72-1.63 (m, 2H), 1.45-1.39 (m, 9H), 1.22 (s, 12H), 0.15-−0.29 (m, 1H).

Step B: tert-Butyl (1R,5S,6r)-6-(6-(tert-butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate. tert-Butyl (1R,5S,6s)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate (200 mg, 0.647 mmol), 2-bromo-6-(tert-butyl)pyridine (166 mg, 0.775 mmol), and Cs₂CO₃ (632 mg, 1.94 mmol) were taken up in 2-methyl-2-butanol (4 mL) and H₂O (1 mL). The resultant mixture was sparged with N₂ for 5 minutes and then treated with CataCXium A Pd G3 (24 mg, 0.033 mmol). The mixture was sparged with N₂ for another 5 minutes and then stirred at 90° C. for 1 hour under microwave irradiation before cooling to room temperature. The reaction mixture was quenched with water and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to afford the crude product, which was purified by FCC (0-13% EtOAc in ether) to afford the title compound as a yellow oil (300 mg, quant.). MS (ESI): mass calcd. for C₁₉H₂₈N₂O₂, 316.2; m/z found, 317.2 [M+H]⁺.

Step C: (1R,5S,6r)-6-(6-(tert-Butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane. tert-Butyl (1R,5S,6r)-6-(6-(tert-butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane-3-carboxylate (300 mg, 0.948 mmol) and TFA (3 mL, 17.7 mmol) in DCM (6 mL) was stirred at room temperature for 30 minutes. The reaction mixture was concentrated under reduced pressure to afford the title compound as a yellow oil (350 mg, crude), which was used in the next step without further purification. MS (ESI): mass calcd. for C₁₄H₂₀N₂, 216.2; m/z found, 217.2 [M+H]⁺.

Step D: (2s,4S)-2-((1R,5S,6R)-6-(6-(tert-Butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. T₃P® (0.83 mL, 50% in ethyl acetate, 1.40 mmol) was added to a solution of 6-(6-(tert-butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane (350 mg, crude, 1.62 mmol), (2s,4s)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carboxylic acid (Intermediate 3, 160 mg, 0.935 mmol), and DIPEA (0.83 mL, 4.70 mmol) in DCM (10 mL). The reaction was stirred at room temperature for 16 hours before being quenched with H₂O and extracted with DCM. The combined organic extracts were dried over anhydrous Na₂SO₄, filtered, and concentrated under reduced pressure to afford the crude product, which was purified by RP-HPLC (38-68% (v/v) CH₃CN in H₂O with 0.05% NH₃+10 mM NH₄HCO₃) to afford the title compound as a white solid (45 mg, 13% yield). MS (ESI): mass calcd. for C₂₁H₂₇N₃O₃, 369.2; m/z found, 370.1 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.50-7.44 (m, 1H), 7.09 (d, J=7.7 Hz, 1H), 6.93 (d, J=7.5 Hz, 1H), 5.94 (br s, 1H), 4.37 (s, 2H), 3.97 (d, J=12.3 Hz, 1H), 3.71-3.63 (m, 2H), 3.58 (dd, J=4.3, 12.3 Hz, 1H), 2.95-2.86 (m, 1H), 2.68-2.60 (m, 2H), 2.57-2.46 (m, 2H), 2.28-2.18 (m, 2H), 1.73 (t, J=3.2 Hz, 1H), 1.30 (s, 9H).

Example 117: (2s,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 58 (Stationary phase: OJ-H, 2×25 cm, Mobile phase: 15% EtOH, 85% CO₂). MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.2; m/z found, 395.2 [M+H]⁺. ¹H NMR (500 MHz, CDCl₃) δ 7.59-7.51 (m, 2H), 7.37-7.29 (m, 2H), 6.03 (d, J=19.4 Hz, 1H), 4.38 (d, J=10.1 Hz, 2H), 4.01-3.90 (m, 1H), 3.87-3.66 (m, 1H), 3.59-3.43 (m, 1H), 3.40-3.21 (m, 1H), 3.06-2.91 (m, 1H), 2.72-2.60 (m, 2H), 2.54-2.44 (m, 2H), 2.23-2.07 (m, 2H), 1.58-1.42 (m, 1H), 1.09 (dt, J=9.0, 5.3 Hz, 1H), 0.87 (q, J=5.3 Hz, 1H).

Example 118: (2s,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 58 (Stationary phase: OJ-H, 2×25 cm, Mobile phase: 15% EtOH, 85% CO₂). MS (ESI): mass calcd. for C₂₀H₂₁F₃N₂O₃, 394.2; m/z found, 395.2 [M+H]⁺. ¹H NMR (500 MHz, CDCl₃) δ 7.55 (d, J=8.1 Hz, 2H), 7.36-7.30 (m, 2H), 6.30 (d, J=14.6 Hz, 1H), 4.38 (d, J=10.0 Hz, 2H), 4.00-3.91 (m, 1H), 3.87-3.66 (m, 1H), 3.58-3.42 (m, 1H), 3.41-3.23 (m, 1H), 3.06-2.91 (m, 1H), 2.73-2.63 (m, 2H), 2.52-2.41 (m, 2H), 2.22-2.07 (m, 2H), 1.58-1.41 (m, 1H), 1.12-1.04 (m, 1H), 0.86 (q, J=5.3 Hz, 1H).

Example 119: (2r,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 52 (Stationary phase: CHIRALPAK AD-H, 5 μm 250×21.2 mm, Mobile phase: 22% EtOH, 78% CO₂). MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₃, 408.2; m/z found, 409.2 [M+H]⁺. ¹H NMR (400 MHz, CDCl₃) δ 7.34-7.28 (m, 1H), 7.20-7.11 (m, 1H), 7.10-7.02 (m, 2H), 5.95 (d, J=12.1 Hz, 1H), 3.94 (d, J=3.8 Hz, 1H), 3.85-3.65 (m, 1H), 3.58-3.21 (m, 2H), 3.00 (dt, J=17.7, 8.4 Hz, 1H), 2.60-2.47 (m, 2H), 2.45-2.32 (m, 4H), 2.28-2.17 (m, 2H), 2.17-2.05 (m, 2H), 1.54-1.39 (m, 1H), 1.06 (dt, J=9.1, 5.7 Hz, 1H), 0.84 (q, J=5.3 Hz, 1H).

Example 120: (2r,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 52 (Stationary phase: CHIRALPAK AD-H, 5 μm 250×21.2 mm, Mobile phase: 22% EtOH, 78% CO₂). MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₃, 408.2; m/z found, 409.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.34-7.28 (m, 1H), 7.18-7.13 (m, 1H), 7.10-7.02 (m, 2H), 5.95 (d, J=11.9 Hz, 1H), 3.94 (d, J=3.7 Hz, 1H), 3.85-3.65 (m, 1H), 3.58-3.20 (m, 2H), 3.00 (dt, J=17.8, 8.4 Hz, 1H), 2.60-2.47 (m, 2H), 2.44-2.32 (m, 4H), 2.26-2.17 (m, 2H), 2.17-2.04 (m, 2H), 1.53-1.38 (m, 1H), 1.06 (dt, J=9.1, 5.6 Hz, 1H), 0.83 (q, J=5.3 Hz, 1H).

Example 121: (2r,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 55 (Stationary phase: CHIRALPAK AD-H, 5 μm 250×30 mm, Mobile phase: 50% MeOH, 50% CO₂). MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₃, 408.2; m/z found, 409.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.26-7.21 (m, 2H), 7.16-7.10 (m, 2H), 6.17-6.05 (m, 1H), 4.00-3.86 (m, 1H), 3.86-3.65 (m, 1H), 3.58-3.39 (m, 1H), 3.40-3.19 (m, 1H), 3.00 (dt, J=18.3, 8.5 Hz, 1H), 2.60-2.48 (m, 2H), 2.44-2.31 (m, 4H), 2.27-2.17 (m, 2H), 2.11 (tt, J=7.6, 4.7 Hz, 2H), 1.50-1.36 (m, 1H), 1.07-0.99 (m, 1H), 0.81 (td, J=5.4, 3.2 Hz, 1H).

Example 122: (2r,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one

The title compound was prepared by chiral supercritical fluid chromatography of Example 55 (Stationary phase: CHIRALPAK AD-H, 5 μm 250×30 mm, Mobile phase: 50% MeOH, 50% CO₂). MS (ESI): mass calcd. for C₂₁H₂₃F₃N₂O₃, 408.2; m/z found, 409.2 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.26-7.20 (m, 2H), 7.17-7.10 (m, 2H), 6.04 (d, J=11.0 Hz, 1H), 4.01-3.86 (m, 1H), 3.85-3.64 (m, 1H), 3.57-3.40 (m, 1H), 3.40-3.19 (m, 1H), 3.00 (dt, J=18.3, 8.4 Hz, 1H), 2.61-2.47 (m, 2H), 2.44-2.30 (m, 4H), 2.27-2.19 (m, 2H), 2.11 (tt, J=8.3, 5.4 Hz, 2H), 1.50-1.36 (m, 1H), 1.03 (dt, J=9.2, 4.8 Hz, 1H), 0.81 (td, J=5.4, 3.2 Hz, 1H).

Example 123: (rac)-(2s,4s)-2-(7-Chloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 1 using 7-chloro-6-phenyl-3-azabicyclo[4.1.0]heptane instead of 1-(p-tolyl)-3-azabicyclo[3.1.0]hexane. MS (ESI): mass calcd. for C₁₉H₂₁ClN₂O₃, 360.1; m/z found, 361.1 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.41-7.32 (m, 2H), 7.32-7.21 (m, 3H), 5.92 (d, J=15.4 Hz, 1H), 4.38 (d, J=20.2 Hz, 2H), 4.17-3.77 (m, 2H), 3.75-3.12 (m, 2H), 3.10-2.86 (m, 2H), 2.72-2.60 (m, 2H), 2.58-2.41 (m, 2H), 2.23-2.06 (m, 2H), 1.93-1.81 (m, 1H).

Example 124: (rac)-(2s,4s)-2-(7,7-Dichloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one

The title compound was prepared in a manner analogous to Example 1 using 7,7-dichloro-6-phenyl-3-azabicyclo[4.1.0]heptane instead of 1-(p-tolyl)-3-azabicyclo[3.1.0]hexane. MS (ESI): mass calcd. for C₁₉H₂₀Cl₂N₂O₃, 394.1; m/z found, 395.0 [M+H]⁺. ¹H NMR (400 MHz, Chloroform-d) δ 7.43-7.33 (m, 2H), 7.34-7.28 (m, 1H), 7.26-7.21 (m, 2H), 5.95 (d, J=16.4 Hz, 1H), 4.38 (d, J=25.5 Hz, 2H), 4.27-3.39 (m, 3H), 3.15-3.03 (m, 1H), 2.95-2.50 (m, 4H), 2.50-2.31 (m, 2H), 2.25-2.08 (m, 2H).

Biological Methods and Data

Biological Example 1. The assay used to measure the in vitro activity of MGL is adapted from the assay used for another serine hydrolase (FAAH) described in Wilson et al., 2003 (A high-throughput-compatible assay for determining the activity of fatty acid amide hydrolase. Wilson S J, Lovenberg T W, Barbier A J. Anal Biochem. 2003 Jul. 15; 318(2):270-5). The assay consists of combining endogenously expressed MGL from HeLa cells with test compounds, adding [glycerol-1,3-³H]-oleoyl glycerol, incubating for one hour, and then measuring the amount of cleaved [1,3-³H]-glycerol that passes through an activated carbon filter. The amount of cleaved, tritiated glycerol passing through the carbon filter is proportional to the activity of the MGL enzyme in a particular well/test condition.

Standard conditions for this assay combine 300 nM [Glycerol-1,3-³H]-oleoyl glycerol with human MGL from HeLa cells and test compounds for one hour, after which the reaction is filtered through activated carbon and tritium is measured in the flow through. The test compound concentration in screening mode is 10 μM, while the highest compound concentration in IC₅₀ assays is determined empirically. MGL is the predominant hydrolase in HeLa cells/cell homogenates. Results are shown in Table 3.

TABLE 3 MGL IC₅₀ Ex # Compound Name (nM) 1 (rac)-(2s,4s)-2-(1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- 5.9 oxa-5-azaspiro[3.4]octan-6-one; 2 (2s,4*R)-2-((1*S,5*R)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3- 17 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 3 (2s,4*S)-2-((1*R,5*S)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3- 8.5 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 4 (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 49 5-azaspiro[3.4]octan-6-one; 5 (rac)-(2s,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- 1.4 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 6 (rac)-(2s,4s)-2-(1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3- 6.9 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 7 (2s,4*S)-2-((1*R,5*S)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane- 5.0 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 8 (2s,4*R)-2-((1*S,5*R)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane- 11 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 9 (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3- 2.2 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 10 (2s,4*S)-2-((1*R,5*S)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane- 2.3 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 11 (2s,4*R)-2-((1*S,5*R)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane- 2.3 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 12 (rac)-(2r,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3- 14 carbonyl)-5-azaspiro[3.4]octan-6-one; 13 (rac)-(2r,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- 9.2 carbonyl)-5-azaspiro[3.4]octan-6-one; 14 (2r,4*S)-2-((1*R,5*S)-1-(4-(tert-Butyl)phenyl)-3- 23 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 15 (2r,4*R)-2-((1*S,5*R)-1-(4-(tert-Butyl)phenyl)-3- 12 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 16 (rac)-(2s,4s)-2-(1-(3-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3- 5.6 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 17 (rac)-(2s,4s)-2-(1-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3- 3.8 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 18 (rac)-(2s,4s)-2-(1-(4-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3- 4.4 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 19 (rac)-(2s,4s)-2-(1-(3-(Trifluoromethoxy)phenyl)-3- 11 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 20 (rac)-(2s,4s)-2-(1-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- 6.5 oxa-5-azaspiro[3.4]octan-6-one; 21 (rac)-(2s,4s)-2-(1-(m-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7- 14 oxa-5-azaspiro[3.4]octan-6-one; 22 (rac)-(2s,4s)-2-(1-(4-(Trifluoromethoxy)phenyl)-3- 16 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 23 (rac)-(2s,4s)-2-(1-(3-(Trifluoromethyl)phenyl)-3- 14 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 24 (rac)-(2s,4s)-2-(1-(4-(Trifluoromethyl)phenyl)-3- 15 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 25 (rac)-(2s,4s)-2-(1-(4-Methyl-3-(trifluoromethyl)phenyl)-3- 3.6 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 26 (rac)-(2s,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3- 1.4 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 27 (rac)-(2r,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3- 9.5 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 28 (rac)-(2s,4s)-2-(1-(4-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3- 1.7 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 29 (rac)-(2s,4s)-2-(1-(3-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3- 1.5 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 30 (rac)-(2s,4s)-2-(1-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane- 2.9 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 31 (rac)-(2s,4s)-2-(1-(3-(1-Methylcyclopropyl)phenyl)-3- 1.1 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 32 (rac)-(2s,4s)-2-(1-(4-Cyclopropyl-2-methylphenyl)-3- 0.35 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 33 (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethyl)phenyl)-3- 2.5 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 34 (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethoxy)phenyl)-3- 3.1 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 35 (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethoxy)phenyl)-3- 6.5 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 36 (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethyl)phenyl)-3- 3.2 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 37 (rac)-(2s,4s)-2-(1-(3-Fluoro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane- 10 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 38 (2s,4S)-2-((1R,5S,6S)-6-(3-(Trifluoromethoxy)phenyl)-3- 21 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 39 (rac)-(2s,4s)-2-(6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa- 20 5-azaspiro[3.4]octan-6-one; 40 (2s,4S)-2-((1R,6S)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7- 136 oxa-5-azaspiro[3.4]octan-6-one; 41 (2s,4R)-2-((1S,6R)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7- 9.6 oxa-5-azaspiro[3.4]octan-6-one; 42 (rac)-(2s,4s)-2-(7,7-Difluoro-6-phenyl-3-azabicyclo[4.1.0]heptane-3- 203 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 43 (rac)-(2s,4s)-2-(6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7- 8.2 oxa-5-azaspiro[3.4]octan-6-one; 44 (2s,4*R)-2-((1*S,6*R)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3- 2.8 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 45 (2s,4*S)-2-((1*R,6*S)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3- 32 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 46 (rac)-(2s,4s)-2-(6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane- 3.7 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 47 (2s,4*R)-2-((1*S,6*R)-6-(3-Fluoro-4-methylphenyl)-3- 21 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 48 (2s,4*S)-2-((1*R,6*S)-6-(3-Fluoro-4-methylphenyl)-3- 1.3 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 49 (rac)-(2s,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3- 1.6 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 50 (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3- 4.2 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 51 (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3- 0.52 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 52 (rac)-(2r,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3- 4.8 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 53 (rac)-(2s,4s)-2-(6-(o-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7- 51 oxa-5-azaspiro[3.4]octan-6-one; 54 (rac)-(2s,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3- 2.5 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 55 (rac)-(2r,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3- 10 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 56 (rac)-(2s,4s)-2-(6-(p-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7- 7.7 oxa-5-azaspiro[3.4]octan-6-one; 57 (rac)-(2s,4s)-2-(6-(3-(Trifluoromethyl)phenyl)-3- 1.9 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 58 (rac)-(2s,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3- 1.4 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 59 (rac)-(2r,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3- 18 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 60 (rac)-(2s,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- 0.0072 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 61 (rac)-(2r,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- 0.25 carbonyl)-5-azaspiro[3.4]octan-6-one; 62 (rac)-(2s,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- 0.019 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 63 (rac)-(2r,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3- 0.41 carbonyl)-5-azaspiro[3.4]octan-6-one; 64 (rac)-(2s,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3- 0.65 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 65 (rac)-(2r,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3- 4.0 carbonyl)-5-azaspiro[3.4]octan-6-one; 66 (rac)-(2s,4s)-2-(6-(4-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3- 0.69 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 67 (rac)-(2s,4s)-2-(6-(3-Chloro-4-methylphenyl)-3- 0.075 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 68 (rac)-(2r,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane- 5.6 3-carbonyl)-5-azaspiro[3.4]octan-6-one; 69 (rac)-(2s,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3- 0.034 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 70 (rac)-(2r,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3- 0.52 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 71 (rac)-(2s,4s)-2-(6-(3-(1-Methylcyclopropyl)phenyl)-3- 0.024 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 72 (rac)-(2s,4s)-2-(6-(4-Cyclopropyl-2-methylphenyl)-3- 2.1 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 73 (rac)-(2s,4s)-2-(6-(3-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3- 0.25 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 74 (rac)-(2s,4s)-2-(6-(4-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3- 0.21 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 75 (rac)-(2s,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3- 0.34 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 76 (rac)-(2r,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3- 2.6 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 77 (rac)-(2s,4s)-2-(l-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa- 241 5-azaspiro[3.4]octan-6-one; 78 (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3- 0.99 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 79 (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3- 7.2 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 80 (2s,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3- 33 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 81 (2r,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3- 206 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 82 (2s,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3- 0.69 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 83 (2r,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3- 2.9 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 84 (2s,4S)-2-((1R,5S,6S)-6-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane- 5.5 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 85 (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethyl)phenyl)-3- 4.4 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 86 (2s,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3- 25 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 87 (2r,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3- 131 carbonyl)-5-azaspiro[3.4]octan-6-one; 88 (2s,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3- 29 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 89 (2r,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3- 178 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 90 (2s,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane- 2.8 3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 91 (2r,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane- 20 3-carbonyl)-5-azaspiro[3.4]octan-6-one; 92 (2s,4S)-2-((1R,5S,6S)-6-(2,3-Dihydro-1H-inden-5-yl)-3- 4.7 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 93 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3- 0.76 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 94 (rac)-(2s,4s)-2-(1-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 3.5 7-oxa-5-azaspiro[3.4]octan-6-one; 95 (2r,4*S)-2-((1*R,5*S)-1-(4-(1-Methylcyclopropyl)phenyl)-3- 7.5 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 96 (2r,4*R)-2-((1*S,5*R)-1-(4-(1-Methylcyclopropyl)phenyl)-3- 8.5 azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 97 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(o-tolyl)-3- 180 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 98 (2s,4S)-2-((1R,5S,6S)-6-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)- 150 7-oxa-5-azaspiro[3.4]octan-6-one; 99 (2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3- 0.64 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 100 (2s,4*R)-2-((1*S,5*R,6*S)-6-(3-(ter/-Butyl)phenyl)-1-methyl-3- 8.3 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 101 (2s,4S)-2-((1R,5S,6S)-6-(3-Isobutylphenyl)-3-azabicyclo[3.1.0]hexane-3- 1.5 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 102 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3,4-Dimethylphenyl)-1-methyl-3- 23 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 103 (2s,4S)-2-((1R,5S,6S)-6-(3-(terl-Butyl)phenyl-5-D)-3- 0.93 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 104 (2s,4S)-2-((1R,5S,6S)-6-(3-(1-Hydroxy-2-methylpropan-2-yl)phenyl)-3- 19 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 105 2-Methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane- 300 2-carbonyl)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoic acid; 106 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(3-(trifluoromethyl)phenyl)- 28 3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 107 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4- 73 (trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 108 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(4-Cyclopropylphenyl)-1-methyl-3- 38 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 109 (2s,4S)-2-((IR,5S,6S)-6-(4-Cyclopropyl-2-methylphenyl)-3- 1.6 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 110 (2s,4S)-2-((1R,5S,6S)-6-(3-Chloro-4-methylphenyl)-3- 17 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 111 (2s,4S)-2-((1R,5S,6S)-6-(3-Ethyl-4-fluorophenyl)-3- 11 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 112 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3- 6.0 (trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5- azaspiro[3.4]octan-6-one; 113 (2s,4S)-2-((1R,5S,6S)-6-(2-Methyl-3-(trifluoromethyl)phenyl)-3- 78 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 114 (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3- 4.1 (trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa- 5-azaspiro[3.4]octan-6-one; 115 (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3- 5.2 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 116 (2s,4S)-2-((1R,5S,6R)-6-(6-(ter/-Butyl)pyridin-2-yl)-3- 5.2 azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 117 (2s,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethyl)phenyl)-3- 22 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 118 (2s,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethyl)phenyl)-3- 1.6 azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 119 (2r,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3- 5.2 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 120 (2r,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3- 23 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 121 (2r,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethoxy)phenyl)-3- 42 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 122 (2r,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethoxy)phenyl)-3- 12 azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; 123 (rac)-(2s,4s)-2-(7-Chloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3- 200 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; and 124 (rac)-(2s,4s)-2-(7,7-Dichloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3- 32 carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one. NT means not tested.

Biological Example 2. In vivo Study of Test Compounds in Shank3B Mouse Behavioral Model of ASD. Wild-type and B6.129-Shank3^(tm2Gfng)/knock-out mice are used for evaluation of test compound effect on behavior including social interaction, repetitive grooming, and ultrasonic vocalization and activity in a urine open-field test as described in Folkes et al., supra, and Kabitzke et al, Genes Brain Behav. 2018, 17, 4-22. Test compound effects are compared to vehicle and to other MGL inhibitor compounds in the WT and knock-out mice. Alternatively, test compounds are evaluated in the fmr1 model of autism spectrum disorder (see Oddi et al., Behav. Brain Res. 2013, 251, 75-84.

Biological Example 3. The behavioral effects of the compound of Example 78 were evaluated using an animal model of autism in a sociability assay after administration of the compound. The sociability assay was conducted using C57BL/6J mice (commerically available from the Jackon Laboratory, Bar Harbor, Me.) as control, and BTBR T⁺ Itpr3^(tf)/mice (referred herein as “BTBR”)(commerically available from the Jackon Laboratory, Bar Harbor, Me.) as an autism model.

The BTBR mice used in Biological Example 3 was derived from the inbred strain BTBR (Black and Tan BRachyury) that carried the mutations a^(t) (nonagouti; black and tan), Itpr3^(tf) (inositol 1,4,5-triphosphate receptor 3; tufted), and T(brachyury). This BTBR strain of mice exhibit a 100% absence of the corpus callosum and a severely reduced hippocampal commissure. (Wahlsten D, 2003 Brain Res). This strain exhibits several symptoms of autism including reduced social interactions, impaired play, low exploratory behavior, unusual vocalizations and high anxiety as compared to other inbred strains. (McFarlane HG, 2008, Gen, Brain Behav; Moy S S, 2007, Behav Br Res, Scattoni M L, 2008, PLos). This strain of mice contains the Trem2S148E allele—a naturally occurring variant at position 48351151-48351152 on Chr 17 (rs108080490 and rs107649577; Ensembl GRCm38.p6). This TC to GA transition results in a serine to glutamic acid substitution at amino acid 148 (S148E).

1. Materials and Methods

1.1 Animals

Thirty (30) C57BL/6J female mice and thirty (30) BTBR female mice (7-8 weeks old) were used in Biological Example 3. Upon arrival, mice were group-housed (4-5/cage) and acclimated for at least 5 days prior to commencing studies. Animals were maintained on a 12 hr light/dark cycle with room temperature maintained at 22±2° C. and approximately 50% humidity and had access to food and water ad libitum until the day before the experiment.

1.2 Substances and Formulation

The two solutions listed in Table 4 were formulated fresh daily for p.o. administration. Both solutions comprise 20% 2-Hydroxypropyl-β-cyclodextrin (HP-3-CD). The solution containing Example 78 is in a concentration of 0.3 mg/mL.

TABLE 4 Test Dose Concentration Volume Solution (mg/kg) (mg/mL) (mL/kg) Excipient Vehicle N/A N/A 10 20% HP-β-CD Example 78 3 0.3 10 20% HP-β-CD

1.3 Experimental Procedures

Each type of mice is divided into two different treatment groups: those orally administered a Vehicle solution, and those orally administered with a solution of Example 78, both prepared according to Table 4 above. The mice were randomly assigned to treatment groups according to Table 5 below. Mice were administered the test article 60 minutes prior to testing.

TABLE 5 Dosing Test Dose Dosing Volume time before Group N Genotype Solution (mg/kg) (mg/ml) (ml/kg) Route testing 1 15 C57BL/6J Vehicle N/A N/A 10 p.o. 60 minutes 2 15 C57BL/6J Example 78 3 0.3 p.o. 60 minutes 3 15 BTBR Vehicle N/A N/A p.o. 60 minutes 4 15 BTBR Example 78 3 0.3 p.o. 60 minutes

Three-Chamber Sociability Test

Experiments were carried out in a gray plastic arena with two clear dividers creating three chambers (each 19 cm×45 cm). Each divider had a cutout allowing the animal to access all three chambers. Two wire cup-like containers were placed in the corner of either end of the arena (right chamber and left chamber). These containers were used to house either stimulus or familiar mice. The arena was placed in a room with dim lighting (˜10 lux). Animals were brought into the room to acclimate for at least 1 hour prior to beginning experiment.

Initially, empty wire cups are placed into the right and left chambers. Each of the C57BL/6J or BTBR mouse was placed into the center chamber and allowed to habituate for 10 minutes to the arena. After the 10-minute habituation and with the animal still in the arena, a first stimulus mouse, which was subsequently considered a familiar mouse, was placed inside one of the wire cups in either the right or left chamber. In the other wire cup, a small object was placed. The placement of the stimulus mouse and small object switched sides across subjects. The C57BL/6J or BTBR mouse was allowed 10 minutes to explore all three chambers. A second stimulus mouse was subsequently placed in the wire cup in the opposite chamber. The first stimulus mouse was considered as familiar mouse. Again, the C57BL/6J or BTBR mouse was allowed 10 minutes to explore all three chambers.

During the latter 10-minute period, activity of each mouse was recorded and analyzed using the Noldus EthoVision™ software, which is a video tracking software that tracks and analyzes the behavior, movement. The following data were record and scored using activity of each mouse for:

(1) Duration and number of direct/active contacts between the test mouse and both wire cups (stimulus vs. familiar); Active contact was defined as mouse stretching towards wire cup within a 3-5 mm area around the cup; and

(2) Duration and number of entries into each chamber; The mouse was considered to have entered the chamber when it's head and front paws have entered the chamber.

A summary of the three-chamber sociability test settings of Biological Example 3 is provided below in Table 6.

TABLE 6 Test Three-chamber sociability test Assessment Social preference Apparatus Three-chamber arena Lighting Dim (~10 lux) Scoring system Noldus Etho Vision Readout Duration and number of contacts with wire cups and entries into each chamber; time spent in each chamber

1.4 Data Analysis

Data were plotted and analyzed using GraphPad Prism (version 9.1.1) software. A two-way analysis of variance (ANOVA) was used to analyze differences in time spent in chamber, duration of interaction, number of entries into each chamber, and frequency of interactions between C57BL/6 and BTBR mice and treatment group. Bonferroni's multiple comparisons test was performed to examine differences between mice and treatment groups. Statistical significance was set at p<0.05.

2. Results and Conclusion

FIGS. 1A-1D provide data from the three-chamber sociability test results comparing social communications of the C57BL/6 or BTBR mouse spent with familiar mouse and stimulus mouse. The bars shown in FIGS. 1A-1D represent mean±SEM. Tables 7 and 8 provide two-way analysis of variance (ANOVA) of the data for the amount of time and the number of entries the C57BL/6 or BTBR mouse and the mice spent exploring familiar mouse chamber and stimulus mouse chamber. Tables 9 and 10 provide two-way analysis of variance (ANOVA) of the data the amount of time and the number of interactions the C57BL/6 or BTBR mouse spent interacting with familiar mouse or stimulus mouse.

FIG. 1A shows the amount of time the C57BL/6 or BTBR mouse spent exploring familiar mouse chamber and stimulus mouse chamber. The data of FIG. 1A shows that there was no significant difference in the amount of time the C57BL/6 mice or BTBR spent in each chamber. Table 7 below provides two-way analysis of variance (ANOVA) of the data for the amount of time the C57BL/6 or BTBR mouse spent exploring familiar mouse chamber and stimulus mouse chamber.

TABLE 7 Bonferroni's multiple ANOVA comparisons Mean 95% CI Adjusted table DF MS F (DFn, DFd) P value test Diff. of diff. P value Interaction 3 9974 F (3, 112) = P = 0.2994 C57BL/6 mice - −29.67 −115.8 >0.9999 1.238 Vehicle to 56.46 Stimulus 1 5464 F (1, 112) = P = 0.4120 C57BL/6 mice - −23.01 −106.2 >0.9999 0.6781 Example 78 to 60.21 Treatment 3 6557 F (3, 112) = P = 0.4889 BTBR mice - 38.99 −41.58 0.8872 group 0.8137 Vehicle to 119.6 Residual 112 8058 BTBR mice - −40.36 −123.6 0.8832 Example 78 to 42.85

FIG. 1B shows the number of entries the C57BL/6 or BTBR mouse entered into familiar mouse chamber and stimulus mouse chamber. There was a significant difference in the number of entries to either the familiar mouse chamber or stimulus mouse chamber between treatment groups (p=0.0002). However, Bonferroni's multiple comparisons test revealed no difference between treatment groups in the number of times the mice entered either chamber (see FIG. 1B). Table 8 below provides two-way analysis of variance (ANOVA) of the data for the number of entries the C57BL/6 or BTBR mouse entered into familiar mouse chamber and stimulus mouse chamber.

TABLE 8 Bonferroni's multiple ANOVA comparisons Mean 95% CI Adjusted table DF MS F (DFn, DFd) P value test Diff. of diff. P value Interaction 3 20.36 F (3, 112) = P = 0.9306 C57BL/6 mice - 5.667 −5.194 0.752 0.1484 Vehicle to 16.53 Stimulus 1 1074 F (1, 112) = P = 0.0061 C57BL/6 mice - 8.133 −2.727 0.2394 7.824 Example 78 to 18.99 Treatment 3 975.7 F (3, 112) = P = 0.0002 BTBR mice - 6 −4.861 0.6541 group 7.108 Vehicle to 16.86 Residual 112 137.3 BTBR mice - 4.133 −6.727 >0.9999 Example 78 to 14.99

Next, FIG. 1C shows the amount of time the C57BL/6 or BTBR mouse spent interacting with familiar mouse or stimulus mouse. There was a significant difference between groups in the amount of time the mice spent interacting with either the familiar mouse or stimulus mouse (p=0.0025) as well as a significant interaction (p=0.0075). Bonferroni's multiple comparisons test revealed that vehicle treated BTBR mice spent more time interacting with the familiar mouse compared to the stimulus mouse (p=0.0025; see FIG. 1C). Table 9 below provides two-way analysis of variance (ANOVA) of the data for the amount of time the C57BL/6 or BTBR mouse spent interacting with familiar mouse or stimulus mouse.

TABLE 9 Bonferroni's multiple ANOVA comparisons Mean 95% CI Adjusted table DF MS F (DFn, DFd) P value test Diff. of diff. P value Interaction 3 3088 F (3, 110) = P = 0.0075 C57BL/6 mice - −10.11 −35.26 >0.9999 4.198 Vehicle to 15.04 Stimulus 1 901.2 F (1, 110) = P = 0.2708 C57BL/6 mice - 2.873 −22.72 >0.9999 1.225 Example 78 to 28.47 Treatment 3 3737 F (3, 110) = P = 0.0025 BTBR mice - 34.94 9.785 0.0025 group 5.080 Vehicle to 60.09 Residual 110 735.7 BTBR mice - −5.578 −31.17 >0.9999 Example 78 to 20.02

Lastly, FIG. 1D shows the number of interactions with the C57BL/6 or BTBR mouse had with familiar mouse or stimulus mouse. There was a significant difference in the frequency of interactions with the familiar versus stimulus mouse between treatment groups (p=0.0213). Bonferroni's multiple comparisons test revealed that BTBR mice had a higher number of interactions with the familiar mouse compared to the stimulus mouse (p=0.0374; see FIG. 2D). Table 10 below provides two-way analysis of variance (ANOVA) of the data for the number of interactions with the C57BL/6 or BTBR mouse had with familiar mouse or stimulus mouse.

TABLE 10 Bonferroni's multiple ANOVA comparisons Mean 95% CI Adjusted table DF MS F (DFn, DFd) P value test Diff. of diff. P value Interaction 3 96238 F (3, 112) = P = 0.1018 C57BL/6 mice - −19.13 −216.7 >0.9999 2.119 Vehicle to 178.4 Stimulus 1 59052 F (1, 112) = P = 0.2566 C57BL/6 mice - 37.87 −159.7 >0.9999 1.300 Example 78 to 235.4 Treatment 3 152697 F (3, 112) = P = 0.0213 BTBR mice - 205.8 8.230 0.0374 group 3.362 Vehicle to 403.4 Residual 112 45424 BTBR mice - −47.07 −244.6 >0.9999 Example 78 to 150.5

As shown in the data discussed above, BTBR mice spent more time interacting and had a great number of interactions with the familiar mouse compared to the stimulus mouse, whereas the control, C57BL/6 mice did not. Treatment with an MGL inhibitor, specifically, the compound of Example 78, normalized this preference in the BTBR mice and brought social interaction behaviors to levels similar to that measured in the control mice. As shown in FIGS. 1C and 1D, the BTBR mice treated with the compound of Example 78 did not show preference to familiar mouse over stimulus mouse. Therefore, the data presented in FIGS. 1C and 1D demonstrate that BTBR mice treated with the compound of Example 78 exhibit reduction in one of the symptoms of autism spectrum disorder. Specifically, this data show that BTBR mice treated with the compound of Example 78 demonstrate improved social interaction (e.g., increased interest in social novelty) as compared to those BTBR mice treated with placebo.

The invention described and claimed herein is not to be limited in scope by the specific embodiments herein disclosed since these embodiments are intended as illustrations of several aspects of this invention. Any equivalent embodiments are intended to be within the scope of this invention. Indeed, various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims. All publications cited herein are incorporated by reference in their entirety. 

What is claimed:
 1. A method of treating autism spectrum disorder in a subject in need thereof comprising administering to the subject a therapeutically effective amount of compound of Formula (I),

wherein X is CH₂ or O; Y is

R¹ is H; R^(2a) and R^(2b) are each H; R³ is 2,3-dihydro-1H-indene; pyridyl substituted with C₁₋₆alkyl; phenyl; or phenyl substituted with one or two members each independently selected from the group consisting of: halo, C₁₋₆alkyl, C₁₋₆alkyl substituted with OH, C₁₋₆alkyl substituted with CO₂H, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, O-phenyl, and C₃₋₆cycloalkyl substituted with CH₃; R^(a) and R^(b) are each independently H or halo; and R^(c) is H or CH₃; or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof.
 2. The method of claim 1, wherein X is CH₂.
 3. The method of claim 1, wherein X is O.
 4. The method of claim 1, wherein Y is


5. The method of claim 1, wherein Y is


6. The method of claim 1, wherein Y is


7. The method of claim 1, wherein R^(a) and R^(b) are each H.
 8. The method of claim 1, wherein R^(a) and R^(b) are each independently H or Cl.
 9. The method of claim 1, wherein R^(a) and R^(b) are each F.
 10. The method of claim 1, wherein R³ is


11. The method of claim 1, wherein R³ is phenyl, or phenyl substituted with one or two members each independently selected from the group consisting of: Cl, F, CH₃, CH₂CH₃, CH(CH₃)₂, C(CH₃)₃, CH₂CH(CH₃)₂, C(CH₃)₂CH₂OH, C(CH₃)₂CH₂CO₂H, CF₃, OCF₃, cyclopropyl, cyclopropyl substituted with CH₃, and O-phenyl.
 12. The method of claim 1, wherein R³ is


13. The method of claim 1, wherein R³ is 3-tert-butylphenyl, 4-tert-butylphenyl, 4-methyl-3-trifluoromethylphenyl, or 3,4-dimethylphenyl.
 14. The method of claim 1, wherein the compound of Formula (I) is selected from: (rac)-(2s,4s)-2-(1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6- one; (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,5*S)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,5*R)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(m-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Fluoro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,6S)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4R)-2-((1S,6R)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(7,7-Difluoro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(o-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(p-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(2,3-Dihydro-1H-inden-5-yl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,5*S)-1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,5*R)-1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R,6*S)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Isobutylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3,4-Dimethylphenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl-5-D)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(1-Hydroxy-2-methylpropan-2-yl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 2-Methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carbonyl)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoic acid; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(4-Cyclopropylphenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Ethyl-4-fluorophenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(2-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6R)-6-(6-(tert-Butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(7-Chloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; and (rac)-(2s,4s)-2-(7,7-Dichloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; and pharmaceutically acceptable salts, isotopes, N-oxides, solvates, and stereoisomers thereof.
 15. The method of claim 1, wherein the compound of Formula (I) is selected from: (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; and (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; and pharmaceutically acceptable salts, isotopes, N-oxides, solvates, and stereoisomers thereof.
 16. The method of claim 1, wherein the compound is a compound of Formula (IA):

wherein X is CH₂ or O; and R³ is phenyl; or phenyl substituted with one or two members each independently selected from the group consisting of: halo, C₁₋₆alkyl, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, O-phenyl, and C₃₋₆cycloalkyl substituted with CH₃; or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof.
 17. The method of claim 1, wherein the compound is a compound of Formula (IB):

wherein X is CH₂ or O; R³ is 2,3-dihydro-1H-indene; pyridyl substituted with C₁₋₆alkyl; or phenyl substituted with one or two members each independently selected from the group consisting of: halo, C₁₋₆alkyl, C₁₋₆alkyl substituted with OH, C₁₋₆alkyl substituted with CO₂H, C₁₋₆haloalkyl, OC₁₋₆haloalkyl and cyclopropyl; and R^(c) is H or CH₃; or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof.
 18. The method of claim 1, wherein the compound is a compound of Formula (IC):

wherein X is CH₂ or O; R³ is phenyl; or phenyl substituted with one or two members each independently selected from the group consisting of: halo, C₁₋₆alkyl, C₁₋₆haloalkyl, OC₁₋₆haloalkyl, C₃₋₆cycloalkyl, and C₃₋₆cycloalkyl substituted with CH₃; and R^(a) and R^(b) are each independently H, Cl or F; or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof.
 19. A method of treating autism spectrum disorder in a subject in need thereof comprising administering to the subject a therapeutically effective amount of a pharmaceutical composition comprising (a) at least one compound of Formula (I) as in claim 1, or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof, and (b) a pharmaceutically acceptable excipient.
 20. The method of claim 19, wherein the pharmaceutical composition comprises at least one compound of Formula (I) is selected from: (rac)-(2s,4s)-2-(1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S)-1-(p-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R)-1-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R)-1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(1-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,5*S)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,5*R)-1-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Cyclopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(m-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Phenoxyphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(2-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Methyl-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(3-Fluoro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,6S)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4R)-2-((1S,6R)-6-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(7,7-Difluoro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(m-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(3-Fluoro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(o-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(p-Tolyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(tert-Butyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Cyclopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(3-Chloro-4-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(3-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Isopropylphenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2r,4s)-2-(6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-Phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(3,4-Dimethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4S)-2-((1R,5S,6S)-6-(4-Isopropylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(2,3-Dihydro-1H-inden-5-yl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(1-(4-Ethylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,5*S)-1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,5*R)-1-(4-(1-Methylcyclopropyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(o-tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(o-Tolyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,5*S,6*R)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,5*R,6*S)-6-(3-(tert-Butyl)phenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Isobutylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(3,4-Dimethylphenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl-5-D)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-(1-Hydroxy-2-methylpropan-2-yl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; 2-Methyl-2-(3-((1R,5S,6S)-3-((2s,4S)-6-oxo-7-oxa-5-azaspiro[3.4]octane-2-carbonyl)-3-azabicyclo[3.1.0]hexan-6-yl)phenyl)propanoic acid; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-6-(4-Cyclopropylphenyl)-1-methyl-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Cyclopropyl-2-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Chloro-4-methylphenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(3-Ethyl-4-fluorophenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(2-Methyl-3-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4*S)-2-((1*R,5*S,6*R)-1-Methyl-6-(4-methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6S)-6-(4-Methyl-3-(trifluoromethoxy)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4S)-2-((1R,5S,6R)-6-(6-(tert-Butyl)pyridin-2-yl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2s,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethyl)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,6*S)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,6*R)-6-(3-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*S)-2-((1*R,6*S)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (2r,4*R)-2-((1*S,6*R)-6-(4-(Trifluoromethoxy)phenyl)-3-azabicyclo[4.1.0]heptane-3-carbonyl)-5-azaspiro[3.4]octan-6-one; (rac)-(2s,4s)-2-(7-Chloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; and (rac)-(2s,4s)-2-(7,7-Dichloro-6-phenyl-3-azabicyclo[4.1.0]heptane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one; and pharmaceutically acceptable salts, isotopes, N-oxides, solvates, and stereoisomers thereof.
 21. The method of claim 1, wherein the autism spectrum disorder is autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS), Asperger's syndrome, Fragile X syndrome, Rett syndrome, childhood disintegrative disorder, Kanner's syndrome, Phelan McDermid Syndrome, Angelman syndrome, SCN2a related autism, SYNGAP related autism, Dub15q related autism, Dyrk1a related autism, GRIN2B related autism, Malan syndrome, ADNP syndrome, or tuberous sclerosis.
 22. The method of claim 21, wherein the autism spectrum disorder is autistic disorder or Asperger's syndrome.
 23. The method of claim 22, wherein administration of the therapeutically effective amount of the compound of Formula (I) improves social interaction of the subject.
 24. The method of claim 23, wherein the improvement of social interaction is an increase of the subject's interest in social novelty.
 25. The method of claim 22, wherein the compound is (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof.
 26. The method of claim 23, wherein the compound is (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof.
 27. The method of claim 24, wherein the compound is (2s,4S)-2-((1R,5S,6S)-6-(3-(tert-Butyl)phenyl)-3-azabicyclo[3.1.0]hexane-3-carbonyl)-7-oxa-5-azaspiro[3.4]octan-6-one or a pharmaceutically acceptable salt, isotope, N-oxide, solvate, or stereoisomer thereof. 